In this video we'll learn how to use the pythagorean theorem, which is a theorem that applies only to right-triangles (triangles that include a 90-degree angle). The pythagorean theorem tells us that the sum of the squares of the lengths of the legs is equal to the sum of the length of the hypotenuse (the longest side).

Streaming video file encoded with permission for digital streaming by Infobase on April 25, 2015.

Pythagorean Theorem: Geometry-Triangles --(3:07).