Math Dictionary / Pythagorean Theorem
Pythagorean Theorem
The Pythagorean theorem says that in a right triangle, a^2 + b^2 = c^2.
GeometryGrade 8Algebra 1GEDSATACT
What it means
The legs are a and b. The hypotenuse, c, is the longest side across from the right angle.
Also called: a squared plus b squared
Examples
| 3^2 + 4^2 = 5^2 |
| 5, 12, 13 is a right-triangle triple |
| Use it to find distance on a coordinate plane |
Common mistake
The formula works for right triangles only.
Try one
Question: A right triangle has legs 6 and 8. What is the hypotenuse?
Show answer
6^2 + 8^2 = 36 + 64 = 100, so c = 10.