Word problems on Pythagorean Theorem

Learn how to solve different types of word problems on Pythagorean Theorem .

Pythagoras Theorem can be used to solve the problems step-by-step when we know the length of two sides of a right angled triangle and we need to get the length of the third side.

Three cases of word problems on Pythagorean Theorem :

Case 1: To find the hypotenuse where perpendicular and base are given.

Case 2: To find the base where perpendicular and hypotenuse are given.

Case 3: To find the perpendicular where base and hypotenuse are given.

Word problems using the Pythagorean Theorem:

1. A person has to walk 100 m to go from position X in the north of east direction to the position B and then to the west of Y to reach finally at position Z. The position Z is situated at the north of X and at a distance of 60 m from X. Find the distance between X and Y.

Let XY = x m

Therefore, YZ = (100 – x) m

In ∆ XYZ, ∠Z = 90°


Therefore, by Pythagoras theorem

XY = YZ + XZ

⇒ x = (100 – x) + 60

⇒ = 10000 – 200x + + 3600

Pythagorean Theorem Word Problem

⇒ 200x = 10000 + 3600

⇒ 200x = 13600

⇒ x = 13600/200

Therefore, distance between X and Y = 68 meters.

Word problems on Pythagorean Theorem

Therefore, length of each side is 8 cm.

Using the formula solve more word problems on Pythagorean Theorem.

3. Find the perimeter of a rectangle whose length is 150 m and the diagonal is 170 m.

Word problem on Pythagorean Theorem

In a rectangle, each angle measures 90°.

Therefore PSR is right angled at S

Using Pythagoras theorem, we get

⇒ PS = √6400

Therefore perimeter of the rectangle PQRS = 2 (length + width)

                                                          = 2 (150 + 80) m

                                                          = 2 (230) m

                                                          = 460 m

4. A ladder 13 m long is placed on the ground in such a way that it touches the top of a vertical wall 12 m high. Find the distance of the foot of the ladder from the bottom of the wall.

Word problems using the Pythagorean Theorem

Let the required distance be x meters. Here, the ladder, the wall and the ground from a right-angled triangle. The ladder is the hypotenuse of that triangle.

According to Pythagorean Theorem,

Therefore, distance of the foot of the ladder from the bottom of the wall = 5 meters.

5. The height of two building is 34 m and 29 m respectively. If the distance between the two building is 12 m, find the distance between their tops.

Pythagorean Theorem: Word Problems

The vertical buildings AB and CD are 34 m and 29 m respectively.

Draw DE ┴ AB

Then AE = AB – EB but EB = BC

Therefore AE = 34 m - 29 m = 5 m

Now, AED is right angled triangle and right angled at E.

⇒ AD = √169

Therefore the distance between their tops = 13 m.

The examples will help us to solve various types of word problems on Pythagorean Theorem.

Congruent Shapes

Congruent Line-segments

Congruent Angles

Congruent Triangles

Conditions for the Congruence of Triangles

Side Side Side Congruence

Side Angle Side Congruence

Angle Side Angle Congruence

Angle Angle Side Congruence

Right Angle Hypotenuse Side congruence

Pythagorean Theorem

Proof of Pythagorean Theorem

Converse of Pythagorean Theorem

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15 Pythagorean Theorem Practice Problems For 8th Grade

Beki Christian

Pythagorean Theorem practice problems involve using the relationship between the sides of a right triangle to calculate missing side lengths in triangles. The Pythagorean Theorem is introduced in 8th grade and is used to solve a variety of problems across high school.

Here, you’ll find a selection of Pythagorean Theorem questions that demonstrate the different types of questions students are likely to encounter in 8th grade.

What is the Pythagorean Theorem?

The Pythagorean Theorem is the geometric theorem that states that the square of the hypotenuse (longest side) of a right triangle is equal to the sum of the squares of the two shorter sides of the triangle.

This can be written as a^2+b^2=c^2 for a triangle labeled like this:

15 Pythagoras Theorem image 1

15 Pythagoras Theorem Practice Problems

Find all of the Pythagoras Theorem questions included in this blog in this easy to download resource. Suitable for 8th grade students. Includes answer key.

How to answer Pythagorean Theorem questions

1 – Label the sides of the triangle a , b , and c . Note that the hypotenuse, the longest side of a right triangle, is opposite the right angle and will always be labeled .

15 Pythagoras Theorem image 2

2 – Write down the formula and substitute the values>

3 – Calculate the answer. You may be asked to give your answer in an exact form or round to a given degree of accuracy, such as a certain number of decimal places or significant figures.

Pythagorean Theorem in real life

Pythagorean Theorem has many real-life uses, including in architecture and construction, navigation and surveying.

Pythagorean Theorem in 8th grade

Pythagorean Theorem is usually introduced in middle school, as it is a part of the 8th grade Common Core Math Standards.

The emphasis in middle school is on students being able to:

  • Explain the Pythagorean Theorem;
  • Use the theorem to solve mathematical and real-world problems – with both 2D and 3D figures;
  • Use the theorem to calculate the distance between two points on a coordinate grid.

The process for solving any Pythagoras Theorem problem always begins by identifying the relevant right-angled triangle and labeling the sides a , b , c. If there is not a diagram in the question, it can be helpful to draw one.

Where necessary, round your answers to 3 significant figures.

Pythagorean Theorem practice problems

1. A ship sails 6 \, km East and then 8 \, km North. Find the ship’s distance from its starting point.

15 Pythagoras Theorem question 1

The ship is 10 kilometers from its starting point.

2. A ladder is 5 \, m long. The base of the ladder is 3 \, m from the base of a vertical wall. How far up the wall does the ladder reach?

15 Pythagoras Theorem question 2

The ladder reaches 4 meters up the wall.

3. Alex and Sam start from the same point. Alex walks 400 meters west. Sam walks x meters south, until they are 600 \, m apart from each other. How far does Sam walk?

problem solving on pythagorean theorem

4. A television’s size is the measurement from the upper left hand corner of the television to the bottom right hand corner. Find the size of this television.

15 Pythagoras Theorem question 4

39.7 inches

55.1 inches

15 Pythagoras Theorem answer 4

5. The pole of a sailing boat is supported by a rope from the top of the pole to an anchor point on the deck. The pole is 4 \, m long and the rope is 4.5 \, m long. Calculate the distance from the base of the pole to the anchor point of the rope on the deck.

15 Pythagoras Theorem question 5

6. Work out the length of the diagonal of a square with 8 \, cm sides.

15 Pythagoras Theorem answer 6

The diagonal of the square has a length of 11.3 centimeters.

7. ABC is an isosceles triangle.

15 Pythagoras Theorem question 7

Work out the height of the triangle.

15 Pythagoras Theorem answer 7

8. ABCD is an isosceles trapezoid.

15 Pythagoras Theorem question 8

Work out the length of AD.

15 Pythagoras Theorem answer 8

9. Here is a cm square grid. Calculate the distance between the points A and B.

15 Pythagoras Theorem question 9

10. Which is a right angled triangle?

15 Pythagoras Theorem question 10

Not a right angled triangle because Pythagorean Theorem doesn’t work.

Right angled triangle because Pythagorean Theorem works.

11. PQRS is made from two right angled triangles.

15 Pythagoras Theorem question 11

Work out the length of QR.

15 Pythagoras Theorem answer 11

Triangle \text{PQS:}

Triangle \text{QRS}

12. Here is a pattern made from right angled triangles. Work out the length x.

15 Pythagoras Theorem question 12

Triangle \text{ABC:}

Triangle \text{ACD:}

13. Here is a pyramid.

15 Pythagoras Theorem question 13

Work out the height of the pyramid.

15 Pythagoras Theorem answer 13

14. Here is a cuboid.

15 Pythagoras Theorem question 14

Work out the length AG.

Give your answer in its exact form.

15 Pythagoras Theorem answer 14 image 1

Length of \text{BG:}

15 Pythagoras Theorem answer 14 image 2

Length of \text{AG:}

15. Here is a right angled triangle.

Form an equation and use it to work out the value of x.

15 Pythagoras Theorem question 15

x=4 \, or \, x=12

x cannot be 4 as you can’t have a negative side length so x=12

Pythagorean Theorem in middle school

In middle school, students…

  • prove the Pythagorean Theorem;
  • use the Pythagorean Theorem with trigonometric ratios to solve problems;
  • use the Pythagorean Theorem in proofs.

Pythagoras Theorem may feature in questions alongside other topics, such as trigonometry, circle theorems or algebra.

The Pythagorean Theorem is used to calculate a missing length in a right triangle . If you have a right angled triangle and you know two of the lengths, label the sides of the triangle a,b and c (c must be the hypotenuse – the longest side). Pythagorean Theorem is a^2+b^2=c^2. Substitute the values you know into Pythagorean Theorem and solve to find the missing side.

The hypotenuse of a right triangle is the longest side. If you know the lengths of the other two sides, you can find the length of the hypotenuse by squaring the two shorter sides, adding those values together and then taking the square root. By doing this you are finding c in a^2+b^2=c^2

If your triangle is a right triangle and you know two of the sides, you can use Pythagorean Theorem to find the length of the third side. To do this, label the sides a , b and c (with c being the hypotenuse – the longest side). Substitute the values you know into a^2+b^2=c^2 and solve to find the missing side.

Looking for more Pythagorean theorem math questions?

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Do you have students who need extra support in math? Give your students more opportunities to consolidate learning and practice skills through personalized math tutoring with their own dedicated online math tutor. Each student receives differentiated instruction designed to close their individual learning gaps, and scaffolded learning ensures every student learns at the right pace. Lessons are aligned with your state’s standards and assessments, plus you’ll receive regular reports every step of the way. Personalized one-on-one math tutoring programs are available for: – 2nd grade tutoring – 3rd grade tutoring – 4th grade tutoring – 5th grade tutoring – 6th grade tutoring – 7th grade tutoring – 8th grade tutoring Why not learn more about how it works ?

The content in this article was originally written by former UK Secondary teacher Beki Christian and has since been revised and adapted for US schools by elementary and middle school teacher Kathleen Epperson.

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Pythagorean Theorem – Definition, Formula, Problems

Pythagorean Theorem in Math

In mathematic, the Pythagorean theorem states that the square of the hypotenuse of a right triangle is equal to the sum of the squares of its other two sides . Another way of stating the theorem is that the sum of the areas of the squares formed by the sides of a right triangle equals the area of the square whose side is the hypotenuse. The theorem is a key relation in Euclidean geometry. It is named for the Greek philosopher Pythagorus.

Remember: The Pythagorean theorem only applies to right triangles!

Pythagorean Theorem Formula

The formula for the Pythagorean theorem describes the relationship between the sides a and b of a right triangle to its hypotenuse, c . A right triangle is one containing a 90° or right angle. The hypotenuse is the side of the triangle opposite from the right angle (which is the largest angle in a right triangle).

a 2 + b 2 = c 2

Solving for a, b, and c

Rearranging the equation gives the formulas solving for a, b, and c:

  • a = (c 2 – b 2 ) ½
  • b = (c 2 – a 2 ) ½
  • c = (a 2 + b 2 ) ½

How to Solve the Pythagorean Theorem – Example Problems

For example, find the hypotenuse of a right triangle with side that have lengths of 5 and 12.

Start with the formula for the Pythagorean theorem and plug in the numbers for the sides a and b to solve for c .

a 2 + b 2 = c 2 5 2 + 12 2 = c 2 c 2 = 5 2 + 12 2 = 25 + 144 = 169 c2 = 169 c = √169 or 169 ½ = 13

For example, solve for side b of a triangle where a is 9 and the hypotenuse c is 15.

a 2 + b 2 = c 2 9 2 + b 2 = 15 2 b 2 = 15 2 – 9 2 = 225 – 81 = 144 b = √144 = 12

Now, let’s combine a bit of algebra with the geometry. Solve for x where the sides of a right triangle are 5x and 4x +5 and the hypotenuse has a length of 8x -3.

a 2 + b 2 = c 2 (5x) 2 + (4x +5) 2 = (8x-3) 2

The (4x + 5) 2 and (8x -3)2 terms are the squares of binomial expressions. So, expanding the equation gives the following:

25x 2 + (4x +5)(4x +5) = (8x -3)(8x -3) 25x 2 = 16×2 + 20x +20x + 25 = 64x – 24x – 24x + 9

Combine like terms:

41x 2 + 40x + 25 = 64x 2 – 48x + 9

Rewrite the equation and solve for x.

0 = 23x 2 – 88x – 16

Apply the quadratic equation and solve for x:

x = [-b ± √(b 2 -4ac)]/2a x = [-(-88) ± √[-88 2 – 4(23)(-16)] / 2(23) = [88 ± √(7744 + 1472)] / 46 = (88 ± 96) / 46

So, there are two answers:

x = (88 + 96)/46 = 4 and (88 – 96).46 = -4/23

A triangle does not have a negative length for its side, so x is 4.

Plugging in”4″ in place of x, the sides of the right triangle are 20, 21, and 29.

Pythagorean Triples

Pythagorean triples are integers a, b, and c, that represent the sides of a right triangle and satisfy the Pythagorean theorem. Here is the list of Pythagorean triples for integers with values less than 100:

(3, 4, 5), (5, 12, 13), (7, 24, 25), (8, 15, 17), (9, 40, 41), (11, 60, 61), (12, 35, 37), (13, 84, 85), (16, 63, 65), (20, 21, 29), (28, 45, 53), (33, 56, 65), (36, 77, 85), (39, 80, 89), (48, 55, 73), (65, 72, 97)

Proof of the Pythagorean Theorem

There are more proofs for the Pythagorean theorem than for any other theorem in geometry! At least 370 proofs are known. Some of these proofs use the parallel postulate. Some rely on the complementarity of acute angles in a right triangle. Proofs using shearing use the properties of parallelograms.

History – Did Pythagoras Discover the Pythagorean Theorem?

While the Pythagorean theorem takes its name from Pythagorus, he did not discover it. Exactly who gets the credit or whether many different places made the discovery independently is a matter of debate. The Mesopotamians made calculations using the formula as early as 2000 BC, which was over a thousand years before Pythagorus. A papyrus from the Egyptian Middle Kingdom, dating between 2000 and 1786 BC, references a math problem describing Pythagorean triples. The Baudhayana Shulba Sutra from India (dating between the 8th and 5th century BC) lists both Pythagorean triples and the Pythagorean theorem. The “Gougu theorem” from China offers a proof for the Pythagorean theorem, which came into use long before its oldest surviving description from the 1st century BC.

Pythagorus of Samos lived between 570 and 495 BC. While he was not the original person who formulated the Pythagorean theorem, he (or his students) may have introduced its proof to ancient Greece. In any case, his philosophical treatment of math left a lasting impression on the world.

  • Bell, John L. (1999). The Art of the Intelligible: An Elementary Survey of Mathematics in its Conceptual Development . Kluwer. ISBN 0-7923-5972-0.
  • Heath, Sir Thomas (1921). “ The ‘Theorem of Pythagoras ‘”. A History of Greek Mathematics (2 Vols.) (Dover Publications, Inc. (1981) ed.). Oxford: Clarendon Press. ISBN 0-486-24073-8.
  • Maor, Eli (2007). The Pythagorean Theorem: A 4,000-Year History . Princeton, New Jersey: Princeton University Press. ISBN 978-0-691-12526-8.
  • Swetz, Frank; Kao, T. I. (1977). Was Pythagoras Chinese?: An Examination of Right Triangle Theory in Ancient China . Pennsylvania State University Press. ISBN 0-271-01238-2.

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Pythagoras Theorem Questions

Welcome to our Pythagoras' Theorem Questions area. Here you will find help, support and questions to help you master Pythagoras' Theorem and apply it.

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Pythagoras' Theorem Questions

Here you will find our support page to help you learn to use and apply Pythagoras' theorem.

Please note: Pythagoras' Theorem is also called the Pythagorean Theorem

There are a range of sheets involving finding missing sides of right triangles, testing right triangles and solving word problems using Pythagoras' theorem.

Using these sheets will help your child to:

  • learn Pythagoras' right triangle theorem;
  • use and apply the theorem in a range of contexts to solve problems.

Pythagoras' Theorem

where a,b and c are the sides of a right triangle.
Side c is the hypotenuse (longest side).

Pythagoras' Theorem - in more detail

Pythagoras' theorem states that in a right triangle (or right-angled triangle) the sum of the squares of the two smaller sides of the triangle is equal to the square of the hypotenuse.

Right triangle labelled

In other words, \[ a^2 + b^2 = c^2 \]

where c is the hypotenuse (the longest side) and a and b are the other sides of the right triangle.

What does this mean?

This means that for any right triangle, the orange square (which is the square made using the longest side) has the same area as the other two blue squares added together.

Right triangle pythagoras

Other formulas that can be deduced from the Pythagorean theorem

As a result of the formula \[ a^2 + b^2 = c^2 \] we can also deduce that:

  • \[ b^2 = c^2 - a^2 \]
  • \[ a^2 = c^2 - b^2 \]
  • \[ c = \sqrt{a^2 + b^2} \]
  • \[ b = \sqrt {c^2 - a^2} \]
  • \[ a = \sqrt {c^2 - b^2} \]

Pythagarean Theorem Examples

Example 1) find the length of the missing side..

Pythagoras theorem example 1

In this example, we need to find the hypotenuse (longest side of a right triangle).

So using pythagoras, the sum of the two smaller squares is equal to the square of the hypotenuse.

This gives us \[ 4^2 + 6^2 = ?^2 \]

So \[ ?^2 = 16 + 36 = 52 \]

This gives us \[ ? = \sqrt {52} = 7.21 \; cm \; to \; 2 \; decimal \; places \]

Example 2) Find the length of the missing side.

Pythagoras example 2

In this example, we need to find the length of the base of the triangle, given the other two sides.

This gives us \[ ?^2 + 5^2 = 8^2 \]

So \[ ?^2 = 8^2 - 5^2 = 64 - 25 = 39 \]

This gives us \[ ? = \sqrt {39} = 6.25 \; cm \; to \; 2 \; decimal \; places \]

Pythagoras' Theorem Question Worksheets

The following questions involve using Pythagoras' theorem to find the missing side of a right triangle.

The first sheet involves finding the hypotenuse only.

A range of different measurement units have been used in the triangles, which are not drawn to scale.

  • Pythagoras Questions Sheet 1
  • PDF version
  • Pythagoras Questions Sheet 2
  • Pythagoras Questions Sheet 3
  • Pythagoras Questions Sheet 4

Pythagoras' Theorem Questions - Testing Right Triangles

The following questions involve using Pythagoras' theorem to find out whether or not a triangle is a right triangle, (whether the triangle has a right angle).

If Pythagoras' theorem is true for the triangle, and c 2 = a 2 + b 2 then the triangle is a right triangle.

If Pythagoras' theorem is false for the triangle, and c 2 = a 2 + b 2 then the triangle is not a right triangle.

  • Pythagoras Triangle Test Sheet 1
  • Pythagoras Triangle Test Sheet 2

Pythagoras' Theorem Questions - Word Problems

The following questions involve using Pythagoras' theorem to solve a range of word problems involving 'real-life' type questions.

On the first sheet, only the hypotenuse needs to be found, given the measurements of the other sides.

Illustrations have been provided to support students solving these word problems.

  • Pythagoras Theorem Word Problems 1
  • Pythagoras Theorem Word Problems 2

Geometry Formulas

  • Geometry Formula Sheet

Here you will find a support page packed with a range of geometric formula.

Included in this page are formula for:

  • areas and volumes of 2d and 3d shapes
  • interior angles of polygons
  • angles of 2d shapes
  • triangle formulas and theorems

This page will provide a useful reference for anyone needing a geometric formula.

Triangle Formulas

Here you will find a support page to help you understand some of the special features that triangles have, particularly right triangles.

Using this support page will help you to:

  • understand the different types and properties of triangles;
  • understand how to find the area of a triangle;
  • know and use Pythagoras' Theorem.

All the free printable geometry worksheets in this section support the Elementary Math Benchmarks.

  • Geometry Formulas Triangles

Here you will find a range of geometry cheat sheets to help you answer a range of geometry questions.

The sheets contain information about angles, types and properties of 2d and 3d shapes, and also common formulas associated with 2d and 3d shapes.

Included in this page are:

  • images of common 2d and 3d shapes;
  • properties of 2d and 3d shapes;
  • formulas involving 2d shapes, such as area and perimeter, pythagoras' theorem, trigonometry laws, etc;
  • formulas involving 3d shapes about volume and surface area.

Using the sheets in this section will help you understand and answer a range of geometry questions.

How to Print or Save these sheets 🖶

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Pythagorean Theorem Word Problems

In these lessons, we will be looking at how to solve different types of word problems using the Pythagorean Theorem.

Related Pages Pythagorean Theorem Converse Of Pythagorean Theorem Applications Of Pythagorean Theorem More Geometry Lessons

How To Solve Word Problems Using The Pythagorean Theorem?

  • Determine whether the word problem can be modeled by a right triangle.
  • Use the Pythagorean Theorem to find the missing side if you are given two sides.

Example: Shane marched 3 m east and 6 m north. How far is he from his starting point?

Solution: First, sketch the scenario. The path taken by Shane forms a right-angled triangle. The distance from the starting point forms the hypotenuse.

Example: The rectangle PQRS represents the floor of a room.

Ivan stands at point A. Calculate the distance of Ivan from a) the corner R of the room b) the corner S of the room

Example: In the following diagram of a circle, O is the centre and the radius is 12 cm. AB and EF are straight lines.

Find the length of EF if the length of OP is 6 cm.

Examples Of Real Life Pythagorean Theorem Word Problems

Problem 1: A 35-foot ladder is leaning against the side of a building and is positioned such that the base of the ladder is 21 feet from the base of the building. How far above the ground is the point where the ladder touches the building?

Problem 2: The main mast of a fishing boat is supported by a sturdy rope that extends from the top of the mast to the deck. If the mast is 20 feet tall and the rope attached to the deck 15 feet away from the base of the mast, how long is the rope?

Problem 3: If an equilateral triangle has a height of 8, find the length of each side.

Problem 4: Two cyclist start from the same location. One cyclist travels due north and the other due east, at the same speed. Find the speed of each in miles per hour if after two hours they are 17sqrt(2) miles apart.

Problem 5: Two cars start from the same intersection with one traveling southbound while the other travels eastbound going 10 mph faster. If after two hours they are 10sqrt(34) apart, how fast was each car traveling?

Problem 6: A carpet measures 7 feet long and has a diagonal measurement of sqrt(74) feet. Find the width of the carpet.

Problem 7: Jim and Eileen decided to take a short cut through the woods to go to their friend’s house. When they went home they decided to take the long way around the woods to avoid getting muddy shoes. What total distance did they walk to and from their friend’s house? Dimensions are in meters.

Problem 8: Shari went to a level field to fly a kite. She let out all 650 feet of the string and tied it to a stake. Then, she walked out on the field until she was directly under the kite, which was 600 feet from the stake. How high was the kite from the ground?

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Pythagorean Theorem

The pythagorean theorem.

the pythagorean theorem formula a^2+b^2=c^2 where c is the hypotenuse and sides a and b are the shorter sides known as the legs of the right triangle

If we have a right triangle, and we construct squares using the edges or sides of the right triangle (gray triangle in the middle), the area of the largest square built on the hypotenuse (the longest side) is equal to the sum of the areas of the squares built on the other two sides. This is the Pythagorean Theorem in a nutshell. By the way, this is also known as the Pythagoras’ Theorem .

Pythagorean theorem illustrated using areas of squares

Notice that we square (raised to the second power) the variables [latex]a[/latex], [latex]b[/latex], and [latex]c[/latex] to indicate areas. The sum of the smaller squares (orange and yellow) is equal to the largest square (blue).

The Pythagorean Theorem relates the three sides in a right triangle. To be specific, relating the two legs and the hypotenuse, the longest side.

The Pythagorean Theorem can be summarized in a short and compact equation as shown below.

Pythagorean Theorem is simply summarized by the equation c squared equals a squared plus b squared

Definition of Pythagorean Theorem

For a given right triangle, it states that the square of the hypotenuse, [latex]c[/latex], is equal to the sum of the squares of the legs, [latex]a[/latex] and [latex]b[/latex]. That is, [latex]{a^2} + {b^2} = {c^2}[/latex].

For a more general definition, we have:

In right a triangle, the square of longest side known as the hypotenuse is equal to the sum of the squares of the other two sides.

The Pythagorean Theorem guarantees that if we know the lengths of two sides of a right triangle, we can always determine the length of the third side.

Here are the three variations of the Pythagorean Theorem formulas:

pythagorean theorem formula is c equals square root of a^2 plus b^2

Let’s go over some examples!

Examples of Applying the Pythagorean Theorem

Example 1: Find the length of the hypotenuse.

right triangle with legs of 7 inches and 5 inches

Our goal is to solve for the length of the hypotenuse. We are given the lengths of the two legs. We know two sides out of the three! This is enough information for the formula to work.

For the legs, it doesn’t matter which one we assign for [latex]a[/latex] or [latex]b[/latex]. The result will be the same. So if we let [latex]a=5[/latex], then [latex]b=7[/latex]. Substituting these values into the Pythagorean Formula equation, we get

c equals square root of 74

To isolate the variable [latex]c[/latex], we take the square roots of both sides of the equation. That eliminates the square (power of 2) on the right side. And on the left, we simply have a square root of a number which is no big deal.

However, we need to be mindful here when we take the square root of a number. We want to consider only the principal square root or the positive square root since we are dealing with length. It doesn’t make any sense to have a negative length, thus we disregard the negative length!

Therefore, the length of the hypotenuse is [latex]\sqrt {74}[/latex] inches. If we wish to approximate it to the nearest tenth, we have [latex]8.6[/latex] inches.

Example 2: Find the length of the leg.

right triangle with hypotenuse of 9 cm and leg of 7 cm

Just by looking at the figure above, we know that we have enough information to solve for the missing side. The reason is the measure of the two sides are given and the other leg is left as unknown. That’s two sides given out of the possible three.

Here, we can let [latex]a[/latex] or [latex]b[/latex] equal [latex]7[/latex]. It really doesn’t matter. So, for this, we let [latex]a=7[/latex]. That means we are solving for the leg [latex]b[/latex]. But for the hypotenuse, there’s no room for error. We have to be certain that we are assigning [latex]c[/latex] for the length, that is, for the longest side. In this case, the longest side has a measure of [latex]9[/latex] cm and that is the value we will assign for [latex]c[/latex], therefore [latex]c=9[/latex].

Let’s calculate the length of leg [latex]b[/latex]. We have [latex]a=7[/latex] and [latex]c=9[/latex].

c equals 4 times square root of 2

Therefore, the length of the missing leg is [latex]4\sqrt 2[/latex] cm. Rounding it to two decimal places, we have [latex]5.66[/latex] cm.

Example 3: Do the sides [latex]17[/latex], [latex]15[/latex] and [latex]8[/latex] form a right triangle? If so, which sides are the legs and the hypotenuse?

If these are the sides of a right triangle then it must satisfy the Pythagorean Theorem. The sum of the squares of the shorter sides must be equal to the square to the longest side. Obviously, the sides [latex]8[/latex] and [latex]15[/latex] are shorter than [latex]17[/latex] so we will assume that they are the legs and [latex]17[/latex] is the hypotenuse. So we let [latex]a=8[/latex], [latex]b=15[/latex], and [latex]c=17[/latex].

Let’s plug these values into the Pythagorean equation and check if the equation is true.

289 equals 289

Since we have a true statement, then we have a case of a right triangle! We can now say for sure that the shorter sides [latex]8[/latex] and [latex]15[/latex] are the legs of the right triangle while the longest side [latex]17[/latex] is the hypotenuse.

Example 4: A rectangle has a length of [latex]8[/latex] meters and a width of [latex]6[/latex] meters. What is the length of the diagonal of the rectangle?

The diagonal of a rectangle is just the line segment that connects two non-adjacent vertices. In the figure below, it is obvious that the diagonal is the hypotenuse of the right triangle while the two other sides are the legs which are [latex]8[/latex] and [latex]6[/latex].

rectangle with length of 8 meters and width of 8 meters

If we let [latex]a=6[/latex] and [latex]b=8[/latex], we can solve for [latex]c[/latex] in the Pythagorean equation which is just the diagonal.

c=10

Therefore, the measure of the diagonal is [latex]10[/latex] meters.

Example 5: A ladder is leaning against a wall. The distance from the top of the ladder to the ground is [latex]20[/latex] feet. If the base of the ladder is [latex]4[/latex] feet away from the wall, how long is the ladder?

ladder leaning against a wall

If you study the illustration, the length of the ladder is just the hypotenuse of the right triangle with legs [latex]20[/latex] feet and [latex]4[/latex] feet.

Again, we just need to perform direct substitution into the Pythagorean Theorem formula using the known values then solve for [latex]c[/latex] or the hypotenuse.

c equals 4 times square root of 26

Therefore, the length of the ladder is [latex]4\sqrt {26}[/latex] feet or approximately [latex]20.4[/latex] feet.

Example 6: In a right isosceles triangle, the hypotenuse measures [latex]12[/latex] feet. What is the length of each leg?

Remember that a right isosceles triangle is a triangle that contains a 90-degree angle and two of its sides are congruent.

In the figure below, the hypotenuse is [latex]12[/latex] feet. The two legs are both labeled as [latex]x[/latex] since they are congruent.

a right isosceles triangle with hypotenuse of 12 feet and legs of x

Let’s substitute these values into the formula then solve for the value of [latex]x[/latex]. We know that [latex]x[/latex] is just the leg of the right isosceles triangle which is the unknown that we are trying to solve for.

x equals 6 times square root of 2

Therefore, the leg of the right isosceles triangle is [latex]6\sqrt 2[/latex] feet. If we want an approximate value, it is [latex]8.49[/latex] feet, rounded to the nearest hundredth.

Example 7: The diagonal of the square below is [latex]2\sqrt 2[/latex]. Find its area.

square with a diagonal of 2 times square root of 2

We know the area of the square is given by the formula [latex]A=s^2[/latex] where [latex]s[/latex] is the side of the square. So that means we need to find the side of the square given its diagonal. If we look closely, the diagonal is simply the hypotenuse of a right triangle. More importantly, the legs of the right triangle are also congruent.

Since the legs are congruent, we can let it equal to [latex]x[/latex].

right triangle with hypotenuse of 2 times square root of 2 and legs of x

Substitute these values into the Pythagorean Theorem formula then solve for [latex]x[/latex].

x equals 2

We calculated the length of the leg to be [latex]2[/latex] units. It is also the side of the square. So to find the area of the square, we use the formula

[latex]A = {s^2}[/latex]

That means, the area is

[latex]A = {s^2} = {\left( 2 \right)^2} = 4[/latex]

Therefore, the area of the square is [latex]4[/latex] square units.

You might also like these tutorials:

  • Pythagorean Theorem Practice Problems with Answers
  • Pythagorean Triples
  • Generating Pythagorean Triples

Pythagorean Theorem and Problems with Solutions

Explore some simple proofs of the Pythagorean theorem and its converse and use them to solve problems. Detailed solutions to the problems are also presented.


In the figure below are shown two squares whose sides are a + b and c. let us write that the area of the large square is the area of the small square plus the total area of all 4 congruent right triangles in the corners of the large square.


(a + b) = c + 4 (1 / 2) (a b)
Expand the left hand side of the above equality, and simplify the last term on the right
a + b + 2 a b = c + 2 a b
Simplify to obtain
+ b = c a and b are the sides of the right triangle and c is its hypotenuse.



We first start with a right triangle and then complete it to make a rectangle as shown in the figure below which in turn in made up of three triangles.


The fact that the sides of the rectangle are parallel, that gives rise to angles being congruent (equal in size) in all three triangles shown in the figure which leads to the triangles being similar. We first consider triangles ABE and AED which are similar because of the equality of angles. The proportionality of corresponding sides (a in triangle ABE corresponds to c in triangle AED since both faces a right angle, x in triangle ABE corresponds to a in triangle AED both faces congruent (equal) angles) gives
a / c = x / a which may be written as a = c x
We next consider triangles ECD and AED which are similar because of the equality of angles. The corresponding sides are proportional, hence
b / c = y / b which may be written as b = c y
We now add the sides of the equalities a = c x and b = c y to obtain
a + b = c x + c y = c (x + y)
Use the fact that c = x + y to write
a + b = c The converse of the Pythagorean theorem sates that: if a, b and c are the lengths of a triangle with c the longest side and a + b = c then this triangle is a right triangle and c is the length of its hypotenuse.



Find the area of a right triangle whose hypotenuse is equal to 10 cm and one of its sides is 6 cm.


Which of the following may be the lengths of the sides of a right angled triangle?
a) (2 , 3 , 4)    b) (12 , 16 , 20)    c) (3√2 , 3√2 , 6)


The points A(0 , 2), B(-2 , -1) and C(- 1 , k) are the vertices of a right triangle with hypotenuse AB. Find k.


One side of a triangle has a length that is 2 meters less that its hypotenuse and its second side has a length that is 4 meters less that its hypotenuse. Find the perimeter of the triangle.


Find the perimeter of an equilateral triangle whose height is 60 cm.


Calculate the are of a square field whose diagonal is 100 meters.


Find x in the two right triangles figure below.




Given the hypotenuse and one of the sides, we use the Pythagorean theorem to find the second side x as follows


x + 6 = 10
Solve for x
x = √ (10 - 6 ) = 8
Area of the triangle = (1 / 2) height × base
The two sides of a right triangle make a right angle and may therefore be considered as the height and the base. Hence
Area of the triangle = (1 / 2) 6 × 8 = 24 cm


We use the converse of the Pythagorean theorem to solve this problem.
a) (2 , 3 , 4) : 4 is the length of the longest side
2 + 3 = 13
4 = 16
since 2 + 3 is NOT EQUAL to 4 , (2 , 3 , 4) are not the lengths of the sides of a right triangle.

b) (12 , 16 , 20) : 20 is the longest side
12 + 16 = 400
20 = 400
since 12 + 16 is EQUAL to 20 , (12 , 16 , 20) are the lengths of the sides of a right triangle.

c) (3√2 , 3√2 , 6) : 6 is the longest side
(3√2) + (3√2) = 36
6 = 36
(3√2) + (3√2) is EQUAL to 6 , therefore (3√2 , 3√2 , 6) are the length of a right triangle with the length of the hypotenuse equal to 6. Also since two sides have equal length to 3√2, the right triangle is isosceles.


The points A(0 , 2), B(-2 , -1) and C(- 1 , k) are the vertices of a right triangle with hypotenuse AB. Find k.
Use the formula to find the distance squared between two points given by d = (x - x ) + (y - y ) to find the square of the length of the hypotenuse AB and the sides AC and BC.
AB = (-2 - 0) + (-1 - 2) = 13
AC = (-1 - 0) + (k - 2) = k - 4 k + 5
BC = (-1 - (-2)) + (k - (-1)) = k +2 k + 2
AB is the hypotenuse of the triangle, we now use the Pythagorean theorem AB = AC + BC to obtain an equation in k.
13 = k - 4 k + 5 + k + 2 k + 2
2 k - 2 k - 6 = 0
k - k - 3 = 0
Solve for k the above quadratic equation to obtain two solutions k and k given by
k = ( 1 + √ (13) ) / 2 ? 2.30 and k = ( 1 - √ (13) ) / 2 ? - 1.30
There are two possible points C and C that make a right triangle with A and B and whose coordinates are given by:
C (- 1 , 2.30) and C (- 1 , - 1.30)
The graphical interpretation of the solution to this problem is shown below. Solution k corresponds to the "red" right triangle and solution k corresponds to the "blue" right triangle.




Let x be the hypotenuse of the right triangle. One side is x - 2 and the other is x - 4 as shown below. We need to find in order to find that sides and then the perimeter.

Use the Pythagorean to write
x = (x - 2) + (x - 4)
Expand and group to obtain the quadratic equation
x - 12 x + 20 = 0
Solve to find two solutions
x = 2 and x = 10
Calculate the sides and perimeter for each solution
hypotenuse: x = 2 , side 1 : x - 2 = 0 and side 2 : x - 4 = - 2
The sides of a triangle cannot be zero or negative and therefore x = 2 is not a solution to the given problem.
hypotenuse: x = 10 , side 1 : x - 2 = 8 and side 2 : x - 4 = 6
Perimeter = hypotenuse + side 1 + side 2 = 10 + 8 + 6 = 24 units.


An equilateral triangle with side x is shown below with height CH = 60 cm. Since it is an equilateral the height CH split the base (segment) AB into two equal segments of size x / 2.

We use the Pythagorean theorem on triangle CHB (or CHA) to write
x = 60 + ( x / 2)
Expand the above equation and rewrite as
3 x / 4 = 3600
Solve for x and take the positive solution since x is the size of the side of the triangle and must be positive.
x = 40 √3 cm
Perimeter = 3 x = 120 √3 cm


A square of side x and diagonal 100 m is shown below.
Area of the square = x
Use the Pythagorean theorem on the triangle ACD to write
x + x = 100
Solve for x
Area of square = x = 5000 m




We first use the Pythagorean theorem to the right triangle ECD in order to find the length of CD
5 = 3 + CD
Solve for CD
CD = √(25 - 9) = 4
We also know that
FC + CD = 6
Hence
FC = 6 - CD = 2
We now use the Pythagorean theorem to the right triangle EFC to write
x = 3 + FC = 9 + 4 = 13
Solve for
x = √(13)




MathBootCamps

The pythagorean theorem with examples.

The Pythagorean theorem is a way of relating the leg lengths of a right triangle to the length of the hypotenuse, which is the side opposite the right angle. Even though it is written in these terms, it can be used to find any of the side as long as you know the lengths of the other two sides. In this lesson, we will look at several different types of examples of applying this theorem.

Table of Contents

  • Examples of using the Pythagorean theorem
  • Solving applied problems (word problems)
  • Solving algebraic problems

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Applying the Pythagorean theorem (examples)

In the examples below, we will see how to apply this rule to find any side of a right triangle triangle. As in the formula below, we will let a and b be the lengths of the legs and c be the length of the hypotenuse. Remember though, that you could use any variables to represent these lengths.

image showing the pythagorean theorem formula

In each example, pay close attention to the information given and what we are trying to find. This helps you determine the correct values to use in the different parts of the formula.

Find the value of \(x\).

triangle with unknown hypotenuse

The side opposite the right angle is the side labelled \(x\). This is the hypotenuse. When applying the Pythagorean theorem, this squared is equal to the sum of the other two sides squared. Mathematically, this means:

\(6^2 + 8^2 = x^2\)

Which is the same as:

\(100 = x^2\)

Therefore, we can write:

\(\begin{align}x &= \sqrt{100}\\ &= \bbox[border: 1px solid black; padding: 2px]{10}\end{align}\)

Maybe you remember that in an equation like this, \(x\) could also be –10, since –10 squared is also 100. But, the length of any side of a triangle can never be negative and therefore we only consider the positive square root.

In other situations, you will be trying to find the length of one of the legs of a right triangle. You can still use the Pythagorean theorem in these types of problems, but you will need to be careful about the order you use the values in the formula.

Find the value of \(y\).

example where a leg length is unknown

The side opposite the right angle has a length of 12. Therefore, we will write:

\(8^2 + y^2 = 12^2\)

This is the same as:

\(64 + y^2 = 144\)

Subtracting 64 from both sides:

\(y^2 = 80\)

\(\begin{align}y &= \sqrt{80} \\ &= \sqrt{16 \times 5} \\ &= \bbox[border: 1px solid black; padding: 2px]{4\sqrt{5}}\end{align}\)

In this last example, we left the answer in exact form instead of finding a decimal approximation. This is common unless you are working on an applied problem.

Applications (word problems) with the Pythagorean theorem

There are many different kinds of real-life problems that can be solved using the Pythagorean theorem. The easiest way to see that you should be applying this theorem is by drawing a picture of whatever situation is described.

Two hikers leave a cabin at the same time, one heading due south and the other headed due west. After one hour, the hiker walking south has covered 2.8 miles and the hiker walking west has covered 3.1 miles. At that moment, what is the shortest distance between the two hikers?

First, sketch a picture of the information given. Label any unknown value with a variable name, like x.

figure for a word problem with the pythagorean theorem

Due south and due west form a right angle, and the shortest distance between any two points is a straight line. Therefore, we can apply the Pythagorean theorem and write:

\(3.1^2 + 2.8^2 = x^2\)

Here, you will need to use a calculator to simplify the left-hand side:

\(17.45 = x^2\)

Now use your calculator to take the square root. You will likely need to round your answer.

\(\begin{align}x &= \sqrt{17.45} \\ &\approx 4.18 \text{ miles}\end{align}\)

As you can see, it will be up to you to determine that a right angle is part of the situation given in the word problem. If it isn’t, then you can’t use the Pythagorean theorem.

Algebra style problems with the Pythagorean theorem

There is one last type of problem you might run into where you use the Pythagorean theorem to write some type of algebraic expression. This is something that you will not need to do in every course, but it does come up.

A right triangle has a hypotenuse of length \(2x\), a leg of length \(x\), and a leg of length y. Write an expression that shows the value of \(y\) in terms of \(x\).

Since no figure was given, your first step should be to draw one. The order of the legs isn’t important, but remember that the hypotenuse is opposite the right angle.

algebra problem diagram

Now you can apply the Pythagorean theorem to write:

\(x^2 + y^2 = (2x)^2\)

Squaring the right-hand side:

\(x^2 + y^2 = 4x^2\)

When the problem says “the value of \(y\)”, it means you must solve for \(y\). Therefore, we will write:

\(y^2 = 4x^2 – x^2\)

Combining like terms:

\(y^2 = 3x^2\)

Now, use the square root to write:

\(y = \sqrt{3x^2}\)

Finally, this simplifies to give us the expression we are looking for:

\(y = \bbox[border: 1px solid black; padding: 2px]{x\sqrt{3x}}\)

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The Pythagorean theorem allows you to find the length of any of the three sides of a right triangle. It is one of those things that you should memorize, as it comes up in all areas of math, and therefore in many different math courses you will probably take. Remember to avoid the common mistake of mixing up where the legs go in the formula vs. the hypotenuse and to always draw a picture when one isn’t given.

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  • Maths Questions

Pythagoras Theorem Questions

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Pythagoras theorem questions with detailed solutions are given for students to practice and understand the concept. Practising these questions will be a plus point in preparation for examinations. Let us discuss in brief about the Pythagoras theorem.

Pythagoras’ theorem is all about the relation between sides of a right-angled triangle. According to the theorem, the hypotenuse square equals the sum of squares of the perpendicular sides.

= (Perpendicular) + (Base)

Click here to learn the proof of Pythagoras’ Theorem .

Video Lesson on Pythagoras Theorem

problem solving on pythagorean theorem

Pythagoras Theorem Questions with Solutions

Now that we have learnt about the Pythagoras Theorem, lets apply the same by solving the following questions.

Question 1: In a right-angled triangle, the measures of the perpendicular sides are 6 cm and 11 cm. Find the length of the third side.

Let ΔABC be the triangle, right-angled at B, such that AB and BC are the perpendicular sides. Let AB = 6 cm and BC = 11 cm

Then, by the Pythagoras theorem,

AC 2 = AB 2 + BC 2

\(\begin{array}{l}\Rightarrow AC=\sqrt{(AB^{2}+BC^{2})}=\sqrt{6^{2}+11^{2}}\end{array} \)

\(\begin{array}{l}=\sqrt{36+121}=\sqrt{157}\end{array} \)

∴ AC = √157 cm.

Question 2: A triangle is given whose sides are of length 21 cm, 20 cm and 29 cm. Check whether these are the sides of a right-angled triangle.

If these are the sides of a right-angled triangle, it must satisfy the Pythagoras theorem.

We have to check whether 21 2 + 20 2 = 29 2

Now, 21 2 + 20 2 = 441 + 400 = 841 = 29 2

Thus, the given triangle is a right-angled triangle.

If three integers a, b and c are such that a + b = c , then (a, b, c) is called Pythagorean triples.

For any given integer m, (m – 1, 2m, m + 1) is the Pythagorean triplet.

Learn more about .

Question 3: Find the Pythagorean triplet with whose one number is 6.

Now, m 2 + 1 = 9 + 1 = 10

and m 2 – 1 = 9 – 1 = 8

Therefore, the Pythagorean triplet is (6, 8, 10).

Question 4: The length of the diagonal of a square is 6 cm. Find the sides of the square.

Let ABCD be the square, and let AC be the diagonal of length 6 cm. Then triangle ABC is the right-angled triangle such that AB = BC (∵ all sides of a square are equal)

By Pythagoras theorem,

⇒ AC 2 = 2AB 2

⇒ AC = √2 AB

⇒ AB = (1/√2) AC = (1/√2)6 = 3√2 cm.

Question 5: A ladder is kept at a distance of 15 cm from the wall such that the top of the ladder is at the height of 8 cm from the bottom of the wall. Find the length of the wall.

Let AB be the ladder of length x.

Pythagoras theorem question 5

AC 2 + BC 2 = AB 2

\(\begin{array}{l}\Rightarrow AB=\sqrt{AC^{2}+BC^{2}}\end{array} \)

\(\begin{array}{l}\Rightarrow x=\sqrt{8^{2}+15^{2}}=\sqrt{64+225}\end{array} \)

⇒ x = 17 cm

∴ Length of the ladder is 17 cm.

Question 6: Find the area of a rectangle whose length is 144 cm and the length of the diagonal 145 cm.

Let the rectangle be ABCD

Pythagoras theorem question 6

\(\begin{array}{l}\Rightarrow AD=\sqrt{AC^{2}-CD^{2}}=\sqrt{145^{2}-144^{2)}\end{array} \)

⇒ AD = √(21025 – 20736) = √289

⇒ AD = 17 cm

Thus, area of the rectangle ABCD = 17 × 144 = 2448 cm 2 .

  • Properties of Triangles
  • Congruence of Triangles
  • Similar Triangles
  • Trigonometry

Question 7: A boy travels 24 km towards east from his house, then he turned his left and covers another 10 km. Find out his total displacement?

Let the boy’s house is at point O, then to find the total displacement, we have to find OB.

Pythagoras theorem question 7

Clearly, ΔOAB is a right-angled triangle, by Pythagoras theorem,

\(\begin{array}{l} OB=\sqrt{OA^{2}+AB^{2}}=\sqrt{24^{2}-10^{2}}\end{array} \)

⇒ OB = √(576 + 100) = √676

⇒ OB = 26 km.

Question 8: Find the distance between a tower and a building of height 65 m and 34 m, respectively, such that the distance between their top is 29 m.

The figure below shows the situation. Let x be the distance between the tower and the building.

Pythagoras theorem question 8

In right triangle DCE, by Pythagoras theorem,

CE = √(DE 2 – DC 2 ) = √(29 2 – 21 2 )

⇒ x = √(841 – 441) = √400

⇒ x = 20 m.

∴ the distance between the tower and the building is 20 m.

Question 9: Find the area of the triangle formed by the chord of length 10 cm of the circle whose radius is 13 cm.

Let AB be the chord of the circle with the centre at O such that AB = 10 and OA = OB = 13. Draw a perpendicular OM on AB.

Pythagoras theorem question 9

By the property of circle, perpendicular dropped from the centre of the circle on a chord, bisects the chord.

Then, AM = MB = 5 cm.

Now, in right triangle OMB,

OB 2 = OM 2 + MB 2

⇒ OM = √(OB 2 – MB 2 )

⇒ OM = √(13 2 – 5 2 ) = √(169 – 25)

⇒ OM = √144 = 12 cm

Area of triangle OAB = ½ × AB × OM

= ½ × 10 × 12

= 60 cm 2 .

Question 10: Find the length of tangent PT where P is a point which is at a distance 10 cm from the centre O of the circle of radius 6 cm.

Given, OP = 10 cm and OT = 6m.

We have to find the value of PT.

Pythagoras theorem question 10

By the property of tangents, the radius of the circle is perpendicular to the tangent at the point of contact.

Thus, triangle OTP is a right-angled triangle.

∴ by the Pythagoras theorem,

OP 2 = OT 2. + PT 2

⇒ PT = √(OP 2 – OT 2 ) = √(10 2 – 6 2 )

⇒ PT = √(100 – 36) = √64

⇒ PT = 8 cm.

Related Video on Pythagorean Triples

problem solving on pythagorean theorem

Practice Questions on Pythagoras Theorem

1. Find the area of a right-angled triangle whose hypotenuse is 13 cm and one of the perpendicular sides is 5 cm.

2. Find the Pythagorean triplet whose one member is 15.

3. Find the perimeter of a rectangle whose diagonal is 5 cm and one of its sides is 4 cm.

4 if a pole of length 65 cm is kept leaning against a wall such that the pole reaches up to a height of 63 cm on the wall from the ground. Find the distance between the pole and the wall.

5. Find the area of the triangle inscribed within a circle of radius 8.5 cm such that one of the sides of the triangle is the diameter of the circle and the length of the other side is 8 cm.

(Hint: The triangle is formed in semi-circular region and angle of a semi-circle is of 90 o )

Learn about various mathematical concepts in a simple manner with detailed information, along with step by step solutions to all questions, only at BYJU’S. Download BYJU’S – The Learning App to get personalised videos.

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Pythagorean Theorem

$a$

This is generalized by the Pythagorean Inequality and the Law of Cosines .

  • 1.1 Proof 1
  • 1.2 Proof 2
  • 1.3 Proof 3
  • 2 Common Pythagorean Triples
  • 3.1 Introductory
  • 3.2.1 Solution 1 (Bash)
  • 3.2.2 Solution 2 (Using 3-4-5)
  • 3.3.1 Solution (Casework)
  • 4 External links

$ABC$

Common Pythagorean Triples

$a^{2}+b^{2}=c^{2}$

Also, if (a,b,c) are a pythagorean triplet it follows that (ka,kb,kc) will also form a pythagorean triplet for any constant k.

k can also be imaginary.

Introductory

  • 2006 AIME I Problem 1
  • 2007 AMC 12A Problem 10

Sample Problem

$333$

Solution 1 (Bash)

$\sqrt{333^2 + 444^2} = 555$

Solution 2 (Using 3-4-5)

$333-444$

Another Problem

$3$

Solution (Casework)

3 and 4 are the legs. Then 5 is the hypotenuse.

3 is a leg and 4 is the hypotenuse.

There are no more cases as the hypotenuse has to be greater than the leg.

$4+5=9$

External links

  • 122 proofs of the Pythagorean Theorem

Something appears to not have loaded correctly.

Click to refresh .

problem solving on pythagorean theorem

Module 11: Geometry

Using the pythagorean theorem to solve problems, learning outcomes.

  • Use the pythagorean theorem to find the unknown length of a right triangle given the two other lengths

The Pythagorean Theorem is a special property of right triangles that has been used since ancient times. It is named after the Greek philosopher and mathematician Pythagoras who lived around [latex]500[/latex] BCE.

Remember that a right triangle has a [latex]90^\circ [/latex] angle, which we usually mark with a small square in the corner. The side of the triangle opposite the [latex]90^\circ [/latex] angle is called the hypotenuse, and the other two sides are called the legs. See the triangles below.

In a right triangle, the side opposite the [latex]90^\circ [/latex] angle is called the hypotenuse and each of the other sides is called a leg.

Three right triangles are shown. Each has a box representing the right angle. The first one has the right angle in the lower left corner, the next in the upper left corner, and the last one at the top. The two sides touching the right angle are labeled

The Pythagorean Theorem

In any right triangle [latex]\Delta ABC[/latex],

[latex]{a}^{2}+{b}^{2}={c}^{2}[/latex]

where [latex]c[/latex] is the length of the hypotenuse [latex]a[/latex] and [latex]b[/latex] are the lengths of the legs.

A right triangle is shown. The right angle is marked with a box. Across from the box is side c. The sides touching the right angle are marked a and b.

To solve problems that use the Pythagorean Theorem, we will need to find square roots. In Simplify and Use Square Roots we introduced the notation [latex]\sqrt{m}[/latex] and defined it in this way:

[latex]\text{If }m={n}^{2},\text{ then }\sqrt{m}=n\text{ for }n\ge 0[/latex]

For example, we found that [latex]\sqrt{25}[/latex] is [latex]5[/latex] because [latex]{5}^{2}=25[/latex].

We will use this definition of square roots to solve for the length of a side in a right triangle.

Use the Pythagorean Theorem to find the length of the hypotenuse.

Right triangle with legs labeled as 3 and 4.

Step 1. the problem.
Step 2. what you are looking for. the length of the hypotenuse of the triangle
Step 3. Choose a variable to represent it. Let [latex]c=\text{the length of the hypotenuse}[/latex]

Step 4.

Write the appropriate formula.

Substitute.

[latex]{a}^{2}+{b}^{2}={c}^{2}[/latex]

[latex]{3}^{2}+{4}^{2}={c}^{2}[/latex]

Step 5. the equation. [latex]9+16={c}^{2}[/latex]

[latex]25={c}^{2}[/latex]

[latex]\sqrt{25}={c}^{2}[/latex]

[latex]5=c[/latex]

Step 6.

 

[latex]{3}^{2}+{4}^{2}=\color{red}{{5}^{2}}[/latex]

[latex]9+16\stackrel{?}{=}25[/latex]

[latex]25+25\checkmark[/latex]

Step 7. the question. The length of the hypotenuse is [latex]5[/latex].

Use the Pythagorean Theorem to find the length of the longer leg.

Right triangle is shown with one leg labeled as 5 and hypotenuse labeled as 13.

Step 1. the problem.
Step 2. what you are looking for. The length of the leg of the triangle
Step 3. Choose a variable to represent it. Let [latex]b=\text{the leg of the triangle}[/latex]

Label side

Step 4.

Write the appropriate formula. Substitute.

[latex]{a}^{2}+{b}^{2}={c}^{2}[/latex]

[latex]{5}^{2}+{b}^{2}={13}^{2}[/latex]

Step 5. the equation. Isolate the variable term. Use the definition of the square root.

Simplify.

[latex]25+{b}^{2}=169[/latex]

[latex]{b}^{2}=144[/latex]

[latex]{b}^{2}=\sqrt{144}[/latex]

[latex]b=12[/latex]

Step 6.

[latex]{5}^{2}+\color{red}{12}^{2}\stackrel{?}{=}{13}^{2}[/latex]

[latex]25+144\stackrel{?}{=}169[/latex]

[latex]169=169\checkmark[/latex]

Step 7. the question. The length of the leg is [latex]12[/latex].

Kelvin is building a gazebo and wants to brace each corner by placing a [latex]\text{10-inch}[/latex] wooden bracket diagonally as shown. How far below the corner should he fasten the bracket if he wants the distances from the corner to each end of the bracket to be equal? Approximate to the nearest tenth of an inch.

A picture of a gazebo is shown. Beneath the roof is a rectangular shape. There are two braces from the top to each side. The brace on the left is labeled as 10 inches. From where the brace hits the side to the roof is labeled as x.

Step 1. the problem.
Step 2. what you are looking for. the distance from the corner that the bracket should be attached
Step 3. Choose a variable to represent it. Let = the distance from the corner

Step 4.

Write the appropriate formula.

Substitute.

[latex]{a}^{2}+{b}^{2}={c}^{2}[/latex]

[latex]{x}^{2}+{x}^{2}={10}^{2}[/latex]

Step 5. the equation.

Isolate the variable.

Use the definition of the square root.

Simplify. Approximate to the nearest tenth.

[latex]2x^2=100[/latex]

[latex]x^2=50[/latex]

[latex]x=\sqrt{50}[/latex]

[latex]b\approx{7.1}[/latex]

 

Step 6.

[latex]{a}^{2}+{b}^{2}={c}^{2}[/latex]

[latex](\color{red}{7.1})^2+(\color{red}{7.1})^{2}\stackrel{\text{?}}{\approx}{10}^{2}[/latex]

[latex]50.41+50.41=100.82\approx{100}\quad\checkmark[/latex]

Yes.

Step 7. the question. Kelvin should fasten each piece of wood approximately [latex]7.1″[/latex] from the corner.

In the following video we show two more examples of how to use the Pythagorean Theorem to solve application problems.

  • Question ID 146918, 146916, 146914, 146913. Authored by : Lumen Learning. License : CC BY: Attribution
  • Solve Applications Using the Pythagorean Theorem (c only). Authored by : James Sousa (mathispower4u.com). Located at : https://youtu.be/2P0dJxpwFMY . License : CC BY: Attribution
  • Prealgebra. Provided by : OpenStax. License : CC BY: Attribution . License Terms : Download for free at http://cnx.org/contents/[email protected]

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problem solving on pythagorean theorem

Expert Guidance for Your Pythagorean Theorem Questions

Hayley Steele

Two congruent circles with centres at (2,3) and (5,6), which intersect at right angles, have radius equal to?

Theresa Daugherty

State whether the given statement is true or false: 9, 40, 41 is a Pythagorean triplet. True or false

nefg4m

5, 12, 13 is a Pythagorean triplet. True or false

glucidessho

8, 15, 17 is a Pythagorean triplet

hEorpaigh3tR

Based on Pythagorean identities, which equation is true? A. sin 2 ⁡ θ − 1 = cos 2 ⁡ θ B. sec 2 ⁡ θ − tan 2 ⁡ θ = − 1 C. - cos 2 ⁡ θ − 1 = sin 2 ⁡ θ D. cot 2 ⁡ θ − csc 2 ⁡ θ = − 1

Scarlet Marshall

The end rollers of bar AB(1.5R) are constrained to the slot. If roller A has a downward velocity of 1.2 m/s and this speed is constant over a small motion interval, determine the tangential acceleration of roller B as it passes the topmost position. The value of R is 0.5 m.

umthumaL3e

The area of the obtuse angle triangle shown below is: A17.5 sq. units B 25 sq. units C 14 sq. units D 15 sq. units

autreimL8

Replacing x with 1 2 in 2 x 2 will give you an answer of 1.

Neil Sharp

Why does the Pythagorean theorem only work for right triangles?

BertonCO5

7, 24, 25 is a Pythagorean triplet. A.True B.False

Widersinnby7

A bicycle wheel with a 5 inch ray rotates 60 ∘ . What distance has the bicycle traveled?

calcific5z

The legs of a right triangle are 6 and 8 cm. Find the hypotenuse and the area of ​​the triangle.

Karli Kidd

Solve for X. Anlge A=8x+5 Angle B=4 x 2 -10 Angle C= x 2 +2x+10 I know that they equal 180 degrees. However I am drawinga blank on the factoring part of it

obojeneqk

For each of the following, can the measures represent sides ofa right triangle? Explain your answers.a. 3 m, 4 m, 5 mb. 2 c m , 3 c m , 5 c m

on2t1inf8b

A 10-m ladder is leaning against a building. The bottom of theladder is 5-m from the building. How high is the top of theladder?

Ryan Robertson

Pythagorean theorem and its cause I'm in high school, and one of my problems with geometry is the Pythagorean theorem. I'm very curious, and everything I learn, I ask "but why?". I've reached a point where I understand what the Pythagorean theorem is, and I understand the equation, but I can't understand why it is that way. Like many things in math, I came to the conclusion that it is that way because it is; math is the laws of the universe, and it may reach a point where the "why" answers itself. So what I want to know is, is there an explication to why the addition of the squared lengths of the smaller sides is equal to the squared hypotenuse, or is it just a characteristic of the right triangle itself? And is math the answer to itself? Thank you.

kramberol

pythagorean theorem extensions are there for a given integer N solutions to the equations ∑ n = 1 N x i 2 = z 2 for integers x i and zan easier equation given an integer number 'a' can be there solutions to the equation ∑ n = 1 N x i 2 = a 2 for N=2 this is pythagorean theorem

sweetymoeyz

"Pythagorean theorem" for projection onto convex set I'm going through the book on online convex optimization by Hazan, and in the first chapter I saw this assertion (which Hazan calls the "pythagorean theorem"): Let K ⊂ R d be a convex set, y ∈ R d , and x = Π K ( y ) . Then for any z ∈ K we have: ‖ y − z ‖ ≥ ‖ x − z ‖ . It is presented without proof - what is a proof for this? Also, how does it relate to the pythagorean theorem?

Janessa Olson

Non-geometric Proof of Pythagorean Theorem Is there a purely algebraic proof for the Pythagorean theorem that doesn't rely on a geometric representation? Just algebra/calculus. I want to TRULY understand the WHY of how it is true. I know it works and I know the geometric proofs.

2d3vljtq

The Pythagorean theorem and Hilbert axioms Can one state and prove the Pythagorean theorem using Hilbert's axioms of geometry, without any reference to arithmetic? Edit: Here is a possible motivation for this question (and in particular for the "state" part of this question). It is known that the theory of Euclidean geometry is complete. Every true statement in this theory is provable. On the other hand, it is known that the axioms of (Peano) arithmetic cannot be proven to be consistent. So, basically, I ask if there is a reasonable theory which is known to be consistent and complete, and in which the Pythagorean theorem can be stated and proved. In summary, I guess I am asking - can we be sure that the Pythagorean theorem is true? :)

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Pythagorean Theorem: Problems with Solutions

problem solving on pythagorean theorem

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Right Triangles

Rules, Formula and more

Pythagorean Theorem

The sum of the squares of the lengths of the legs equals the square of the length of the hypotenuse .

Usually, this theorem is expressed as $$ A^2 + B^2 = C^2 $$ .

Right Triangle Properties

Right triangle picture

A right triangle has one $$ 90^{\circ} $$ angle ($$ \angle $$ B in the picture on the left) and a variety of often-studied formulas such as:

  • The Pythagorean Theorem
  • Trigonometry Ratios (SOHCAHTOA)
  • Pythagorean Theorem vs Sohcahtoa (which to use)

SOHCAHTOA only applies to right triangles ( more here ) .

sohcahtoa

A Right Triangle's Hypotenuse

The hypotenuse is the largest side in a right triangle and is always opposite the right angle.

Hypotenuse

In the triangle above, the hypotenuse is the side AB which is opposite the right angle, $$ \angle C $$.

Online tool calculates the hypotenuse (or a leg) using the Pythagorean theorem.

Practice Problems

Below are several practice problems involving the Pythagorean theorem, you can also get more detailed lesson on how to use the Pythagorean theorem here .

Find the length of side t in the triangle on the left.

5, 12, 13 right triangle

Substitute the two known sides into the Pythagorean theorem's formula : A² + B² = C²

What is the value of x in the picture on the left?

pythagorean theorem

Set up the Pythagorean Theorem : 14 2 + 48 2 = x 2 2,500 = X 2

$$ x = \sqrt{2500} = 50 $$

Diagram, Pythagorean Theorem

$$ x^2 = 21^2 + 72^2 \\ x^2= 5625 \\ x = \sqrt{5625} \\ x =75 $$

Find the length of side X in the triangle on on the left?

3, 4, 5 right triangle

Substitue the two known sides into the pythagorean theorem's formula : $$ A^2 + B^2 = C^2 \\ 8^2 + 6^2 = x^2 \\ x = \sqrt{100}=10 $$

What is x in the triangle on the left?

pythagorean image

x 2 + 4 2 = 5 2 x 2 + 16 = 25 x 2 = 25 - 16 = 9 x = 3

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Pythagorean Theorem Calculator

Please provide any 2 values below to solve the Pythagorean equation: a 2 + b 2 = c 2 .

a =

pythagorean theorem triangle

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Pythagorean Theorem

The Pythagorean Theorem, also known as Pythagoras' theorem, is a fundamental relation between the three sides of a right triangle. Given a right triangle, which is a triangle in which one of the angles is 90°, the Pythagorean theorem states that the area of the square formed by the longest side of the right triangle (the hypotenuse) is equal to the sum of the area of the squares formed by the other two sides of the right triangle:

pythagorean theorem

In other words, given that the longest side c = the hypotenuse, and a and b = the other sides of the triangle:

a 2 + b 2 = c 2

This is known as the Pythagorean equation, named after the ancient Greek thinker Pythagoras. This relationship is useful because if two sides of a right triangle are known, the Pythagorean theorem can be used to determine the length of the third side. Referencing the above diagram, if

a = 3 and b = 4

the length of c can be determined as:

c = √ a 2 + b 2 = √ 3 2 +4 2 = √ 25 = 5

It follows that the length of a and b can also be determined if the lengths of the other two sides are known using the following relationships:

a = √ c 2 - b 2

b = √ c 2 - a 2

The law of cosines is a generalization of the Pythagorean theorem that can be used to determine the length of any side of a triangle if the lengths and angles of the other two sides of the triangle are known. If the angle between the other sides is a right angle, the law of cosines reduces to the Pythagorean equation.

There are a multitude of proofs for the Pythagorean theorem, possibly even the greatest number of any mathematical theorem.

Algebraic proof:

pythagorean theorem algebraic proof

In the figure above, there are two orientations of copies of right triangles used to form a smaller and larger square, labeled i and ii, that depict two algebraic proofs of the Pythagorean theorem.

In the first one, i, the four copies of the same triangle are arranged around a square with sides c. This results in the formation of a larger square with sides of length b + a, and area of (b + a) 2 . The sum of the area of these four triangles and the smaller square must equal the area of the larger square such that:

(b + a) = c + 4
ab
2

which yields:

c =(b + a) - 2ab
=b + 2ab + a - 2ab
=a + b

which is the Pythagorean equation.

ab
2
(b - a) + 4
ab
2

Since the larger square has sides c and area c 2 , the above can be rewritten as:

c 2 = a 2 + b 2

which is again, the Pythagorean equation.

There are numerous other proofs ranging from algebraic and geometric proofs to proofs using differentials, but the above are two of the simplest versions.

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April 10, 2023

2 High School Students Have Proved the Pythagorean Theorem. Here’s What That Means

At an American Mathematical Society meeting, high school students presented a proof of the Pythagorean theorem that used trigonometry—an approach that some once considered impossible

By Leila Sloman

The Pythagorean theorem written on a chalkboard

The Pythagorean theorem lets you calculate the longer side of a right triangle by summing the squares of the other two sides.

desifoto/Getty Images

Two high school students have proved the Pythagorean theorem in a way that one early 20th-century mathematician thought was impossible: using trigonometry.

Calcea Johnson and Ne’Kiya Jackson, both at St. Mary’s Academy in New Orleans, announced their achievement last month at an American Mathematical Society meeting. “It’s an unparalleled feeling, honestly, because there’s just nothing like it, being able to do something that ... people don’t think that young people can do,” Johnson told WWL-TV , a New Orleans CBS affiliate.

If verified, Johnson and Jackson’s proof would contradict mathematician and educator Elisha Loomis, who stated in his 1927 book The Pythagorean Proposition that no trigonometric proof of the Pythagorean theorem could be correct. Their work joins a handful of other trigonometric proofs that were added to the mathematical archives over the years. Each sidestepped “circular logic” to prove the pivotal theorem. So what exactly is a trigonometric proof of the Pythagorean theorem, and why was Loomis so closed off to the idea?

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The Pythagorean theorem provides an equation to calculate the longer side of a right triangle by summing the squares of the other two sides. It is often phrased as a 2 + b 2 = c 2 . In this equation, a, b and c represent the lengths of the three sides of a right triangle, a triangle with a 90-degree angle between two of its sides. The quantity c is the length of the longest side, called the hypotenuse. Though the theorem is named for the ancient Greek philosopher Pythagoras, some historians believe it was known in Babylon around 1,000 years earlier.

The theorem “connects algebra and geometry,” says Stuart Anderson, a professor emeritus of mathematics at Texas A&M University–Commerce. “The statement a 2 + b 2 = c 2 , that’s an algebraic statement. But the figure that it comes from is a geometric one.”

Meanwhile trigonometry focuses on functions that depend on angles . These functions, such as the sine and cosine, are defined using right triangles. Imagine a right triangle with one side that lies flat against a table and another that shoots straight up from where it meets the first side at a right angle. The hypotenuse will reach diagonally between these two sides.

Now measure the angle between the hypotenuse and the table. Mathematicians define the sine of this angle as the height of the vertical side divided by the length of the hypotenuse. The cosine of this angle is the length of the horizontal side divided by the hypotenuse. The Pythagorean theorem is therefore equivalent to the equation sin 2 x + cos 2 x = 1. “A lot of the basic trig ‘identities’ are nothing more than Pythagoras’ theorem,” explains Anderson, referring to equations that describe relationships among different trigonometric functions .

Loomis believed that if you used these functions in a proof of the Pythagorean theorem, you would have assumed the theorem to begin with—a circular argument and thus an unforgivable mathematical error.

But that’s not always true. In their talk at the American Mathematical Society meeting, Jackson and Johnson said a trigonometric identity called the law of sines didn’t depend on the Pythagorean theorem and that they could use it to prove the theorem.

Anderson hopes that Jackson and Johnson’s proof will raise interest in mathematics among students. “It kind of makes me wish I still had a class so I could talk about it,” he says.

The other trigonometric proofs of the theorem that have appeared in the past include a few that are described on mathematician Alexander Bogomolny’s website . One of these was crafted by Jason Zimba , then a physicist and mathematician at Bennington College, and published in Forum Geometricorum in 2009. This proof used a trigonometric identity that allows you to calculate the cosine and sine of an angle x – y without using the Pythagorean theorem—if you know the cosines and sines of x and y on their own.

On October 26, 2009 , Bogomolny added Zimba’s proof to his website, writing “Elisha Loomis, myself and no doubt many others believed and still believe that no trigonometric proof of the Pythagorean theorem is possible.... I happily admit to being in the wrong.” Over time, Bogomolny added more trigonometric proofs to the site: one such proof could be written in just four lines.

The saga shows how even the simplest mathematics can surprise us. “Mathematicians, I think, have learned to not make a bold claim that something is impossible because we’ve been embarrassed over the years too many times by doing that,” Anderson says.

The American Mathematical Society has encouraged the New Orleans students to submit their proof for publication in a peer-reviewed scientific journal.

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Charles barkley keeps $1m promise after 2 new orleans students solve pythagorean theorem.

problem solving on pythagorean theorem

NBA Hall of Famer Charles Barkley has donated $1 million to an academy in New Orleans that just produced two groundbreaking young mathematicians.

The story begins last year when GNN reported on the success of two high school teens 2,000 years in the making.

Calcea Johnson and Ne’Kiya Jackson from St. Mary’s Academy in New Orleans said they had solved the Pythagorean Theorem using trigonometry. Classical Greek brainiac Pythagoras created a theorem that goes like this.

The area of the square whose side is the hypotenuse (the side opposite the right angle) is equal to the sum of the areas of the squares on the other two sides. It is written as a2+b2=c2.

One of the interesting things about this bedrock mathematical equation is that for 2,000 years, no mathematician has been able to demonstrate the truth of it without simply using the equation itself as proof; what is called circular logic, and not accepted as true evidence of proof.

Johnson and Jackson reference Elisha Loomis’s  The Pythagorean Proposition , a book investigating this concept, which “flatly states that ‘there are no trigonometric proofs because all the fundamental formulae of trigonometry are themselves based upon the truth of the Pythagorean Theorem,’” the girls wrote.

Following up on this 2,000-year-old conundrum, the two young women presented findings of the ‘Law of Sines,’ which they say proves fundamental truths in trigonometry without relying on the trigonometric equations themselves as evidence.

This accomplishment, which was featured on CBS’ 60 Minutes, piqued the inspiration of Charles Barkley, who announced that he would give the academy a $1 million grant to help the institution continue to hone the talents of students like Jackson and Johnson.

“[Barkley] has a love and passion for what the academy stands for and how it is shaping the lives and futures of young girls in New Orleans,” a representative of the academy said, according to Nola .

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“This transformative gift will assist students as they excel and achieve whatever dream they create within the walls of St. Mary’s Academy,” the academy’s president Pamela Rogers, said in a press release.

Barkley, who will be donating $100K every year for ten years, recently made GNN headlines for turning down broadcasting contracts totaling $100 million that would have required him to leave TNT Sports after it lost the rights to broadcast the NBA.

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Entering the last year of NBA coverage, Barkley stayed on to ensure that all the staff who produce his television work keep their jobs until the end of the 2024-2025 NBA season.

“I love my TNT Sports family,” Barkley said in  a statement released by Turner.  “My #1 priority has been and always will be our people and keeping everyone together for as long as possible.”

SHARE This Generous Man And These Genious Young Women With Your Friends…

Thanks to Mr. Barkley for keeping his word and for the two young women who solved the Pythagorean theorem. We need good mathematicians for our future. Many thanks to both Mr. Barkley and Calcea Johnson and Ne’Kiya Jackson!

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  1. Pythagorean Theorem Practice Problems With Answers

    Here are eight (8) Pythagorean Theorem problems for you to solve. You might need to find either the leg or the hypotenuse of the right triangle. These problems vary in type and difficulty, providing you an opportunity to level up your skills. ... Pythagorean Theorem Practice Problems with Answers. There are eight (8) problems here about the ...

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    Example 2 (solving for a Leg) Use the Pythagorean theorem to determine the length of X. Step 1. Identify the legs and the hypotenuse of the right triangle. The legs have length 24 and X X are the legs. The hypotenuse is 26. Step 2. Substitute values into the formula (remember 'C' is the hypotenuse). A2 + B2 = C2 x2 + 242 = 262 A 2 + B 2 = C 2 x ...

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    Word problems using the Pythagorean Theorem: 1. A person has to walk 100 m to go from position X in the north of east direction to the position B and then to the west of Y to reach finally at position Z. The position Z is situated at the north of X and at a distance of 60 m from X. Find the distance between X and Y. Solution:

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    Pythagorean Theorem in 8th grade. Pythagorean Theorem is usually introduced in middle school, as it is a part of the 8th grade Common Core Math Standards. The emphasis in middle school is on students being able to: Explain the Pythagorean Theorem; Use the theorem to solve mathematical and real-world problems - with both 2D and 3D figures;

  5. Pythagorean Theorem

    How to Solve the Pythagorean Theorem - Example Problems. For example, find the hypotenuse of a right triangle with side that have lengths of 5 and 12. Start with the formula for the Pythagorean theorem and plug in the numbers for the sides a and b to solve for c. a 2 + b 2 = c 2 5 2 + 12 2 = c 2 c 2 = 5 2 + 12 2 = 25 + 144 = 169 c2 = 169 c ...

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    a) d) 8) A right triangle has legs of 52.6 cm and 35.7 cm. Determine the length of the triangle's hypotenuse. 9) A right triangle has a hypotenuse of 152.6 m. The length of one of the other sides is 89.4 m. Determine the length of the third side. 10) For each of the following, the side lengths of a triangle are given.

  7. Pythagoras Theorem Questions

    Other formulas that can be deduced from the Pythagorean theorem. As a result of the formula \[ a^2 + b^2 = c^2 \] we can also deduce that: \[ b^2 = c^2 - a^2 \] ... The following questions involve using Pythagoras' theorem to solve a range of word problems involving 'real-life' type questions. On the first sheet, only the hypotenuse needs to be ...

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    Find the length of EF if the length of OP is 6 cm. Solution: OE is the radius of the circle, which is 12 cm. OP 2 + PE 2 = OE 2. 6 2 + PE 2 = 12 2. PE =. EF = 2 × PE = 20.78 cm. Examples Of Real Life Pythagorean Theorem Word Problems. Problem 1: A 35-foot ladder is leaning against the side of a building and is positioned such that the base of ...

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    The Pythagorean Theorem can be summarized in a short and compact equation as shown below. For a given right triangle, it states that the square of the hypotenuse, In right a triangle, the square of longest side known as the hypotenuse is equal to the sum of the squares of the other two sides. The Pythagorean Theorem guarantees that if we know ...

  10. Pythagoras Practice Questions

    Click here for Answers. . Practice Questions. Previous: Rotations Practice Questions. Next: Direct and Inverse Proportion Practice Questions. The Corbettmaths Practice Questions on Pythagoras.

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    Detailed Solutions to the Above Problems. Solution to Problem 1. Given the hypotenuse and one of the sides, we use the Pythagorean theorem to find the second side x as follows. x 2 + 6 2 = 10 2. Solve for x. x = √ (10 2 - 6 2) = 8. Area of the triangle = (1 / 2) height × base.

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    Solution. The side opposite the right angle is the side labelled \ (x\). This is the hypotenuse. When applying the Pythagorean theorem, this squared is equal to the sum of the other two sides squared. Mathematically, this means: \ (6^2 + 8^2 = x^2\) Which is the same as: \ (100 = x^2\) Therefore, we can write:

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    Practice Questions on Pythagoras Theorem. 1. Find the area of a right-angled triangle whose hypotenuse is 13 cm and one of the perpendicular sides is 5 cm. 2. Find the Pythagorean triplet whose one member is 15. 3. Find the perimeter of a rectangle whose diagonal is 5 cm and one of its sides is 4 cm.

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    The Pythagorean Theorem is one of the most frequently used theorems in geometry, and is one of the many tools in a good geometer's arsenal. A very large number of geometry problems can be solved by building right triangles and applying the Pythagorean Theorem. This is generalized by the Pythagorean Inequality and the Law of Cosines .

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    To solve problems that use the Pythagorean Theorem, we will need to find square roots. In Simplify and Use Square Roots we introduced the notation √m m and defined it in this way: If m= n2, then √m = n for n ≥0 If m = n 2, then m = n for n ≥ 0. For example, we found that √25 25 is 5 5 because 52 =25 5 2 = 25.

  16. Pythagorean Theorem Practice Problems and Examples

    kramberol 2022-07-11. pythagorean theorem extensions. are there for a given integer N solutions to the equations. ∑ n = 1 N x i 2 = z 2. for integers x i and zan easier equation given an integer number 'a' can be there solutions to the equation. ∑ n = 1 N x i 2 = a 2. for N=2 this is pythagorean theorem.

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    Calculate the total area of the plot. Answer: square kilometers. It is given the length of the diagonal of the square. It divides it into two equal triangles. In addition, the two triangles are right and the legs of the same length. be the length of square side and by the Pythagorean theorem we get: \displaystyle x^ {2} +x^ {2}=\left (2\sqrt {2 ...

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  20. PDF Worksheet #1

    Worksheet #1 - Word Problems Pythagorean Theorem Directions: Solve by drawing a picture, identifying a, b, and c, and applying the Pythagorean Theorem. Do not forget to give your answer with units and show ALL your work to receive full credit. 1. Two sides of a right triangle are 8 inches and 12 inches. a.

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    Pythagorean theorem - practice problems. The Pythagorean Theorem states that in a right-angled triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the lengths of the other two sides. This can be written as: where c is the length of the hypotenuse, and a and b are the ...

  22. Pythagorean Theorem Calculator

    a 2 + b 2 = c 2. This is known as the Pythagorean equation, named after the ancient Greek thinker Pythagoras. This relationship is useful because if two sides of a right triangle are known, the Pythagorean theorem can be used to determine the length of the third side. Referencing the above diagram, if. a = 3 and b = 4.

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    Classical Greek brainiac Pythagoras created a theorem that goes like this. The area of the square whose side is the hypotenuse (the side opposite the right angle) is equal to the sum of the areas ...