Home
#### Algebra and Pre-Algebra Lessons

Algebra 1 | Pre-Algebra | Practice Tests | Algebra Readiness Test
#### Algebra E-Course and Homework Information

Algebra E-course Info | Log In to Algebra E-course | Homework Calculator
#### Formulas and Cheat Sheets

Formulas | Algebra Cheat Sheets

Home » Quadratic Equations » Pythagorean Theorem

# Pythagorean Theorem

## The Pythagorean Theorem

## Example 1

## Example 2

This man, is Pythagoras. He was one of the first Greek Mathematicians. He discovered an amazing property of the **right triangle** that we all now know and love as the **Pythagorean Theorem**.

This theorem is well known in Algebra and we study it in our Quadratics unit because we are working with squared terms. Take a look.

In any **right triangle**, the sum of the squares of the legs (2 shorter sides) is equal to the square of the hypotenuse (the longest side).

Please Note: This theorem **ONLY** works for **Right Triangles**.

Let's start by taking a look at an example where we need to find the hypotenuse.

In a right triangle, the length of one leg is 6 cm and the length of the other leg is the square root of 13 cm. Find the length of the hypotenuse.

Now let's look at an example of a problem where we are asked to find the length of a leg of a right triangle.

**A ladder that is 16.5 feet tall is placed against the side of a tree. The base of the tree to the top of the ladder is a distance of 14 feet. How far is the ladder placed away from the base of the tree?**

If word problems confuse you, the best thing you can do is **draw a picture!**

Are you ready to try one?

**1. One leg of a right triangle is 18 inches long. The hypotenuse is 24 inches long. Find the length of the other leg**.

Great Job! Now you are ready to continue your exploration of quadratic equations.

Quadratic Equations Unit

Sign Up for Algebra Class E-courses

Click here to retrieve a lost password.

Custom Search

Most Popular Pages

*"I'd like to start off by relaying my sincerest gratitude for your dedication in teaching algebra. Your methodology is by far the simplest to follow, primarily because you take the time to include the small steps in between that most other teachers leave out.*

*It helps to know why you are doing something. I am 45 and heading to college to get my BS in Business. I need to brush up, hence the visit to your site. Great Job!"*

Jimmy - United States

*"I stumbled onto your site after I found out that I needed to use some fundamental algebra for an assignment. Turns out I had forgotten some things and your great site helped me remember them like "that" (snap of fingers). The organization of the site let me find exactly what I was looking for so easily. Kudos to you for maintaining such a great resource for students of all ages!"*

Tom - United States

*"I just wanted to write and basically thank you for making such a wonderful website! I'm 20 years old and about to take a basic placement test for college. I wanted to brush up on my Algebra skills and I stumbled upon your site. I'm amazed at how simple you make it and how fast I'm remembering Algebra! I don't remember getting most of the answers right when I had an actual teacher in front of me teaching this. Thanks a lot!"*

Elizabeth - United States

*"I am a pensioner living in South Africa. I stumbled on your website, the best thing that could ever happen to me! Your course in Algebra has helped me a lot to better understand the different concepts. Thank you very much for sharing your skills for teaching math to even people like me. Please do not stop, as I am sure that your teachings have helped thousands of people like me all over the world."*

Noel - South Africa

*This is an amazing program. In one weekend I used it to teach my Grade 9 daughter most of the introductory topics in Linear Relations. I took her up to Rate of Change and now she can do her homework by herself.*

Reg - United States

- Algebra Class E-course
- Algebra Class Products
- Print this Site
- Algebra Practice Test
- Algebra Readiness Test
- Homework Answer Calculator
- Practice Worksheets

- Site Map
- Pre-algebra Refresher
- Solving Equations
- Graphing Equations
- Writing Equations
- Systems of Equations
- Inequalities
- Functions
- Exponents & Monomials
- Polynomials
- Quadratic Equations
- Algebra 1 Final Exam

? ## Subscribe To This Site

Then why not use the button below, to add us to your favorite bookmarking service?

Copyright © 2009-2014 Karin Hutchinson ALL RIGHTS RESERVED

## Comments

We would love to hear what you have to say about this page!