How To: Apply the Pythagorean theorem

Meet the Pythagorean theorem—an indispensable tool for any budding geometer. The Pythagorean theorem will allow you to measure the hypotenuse or any other side of a right triangle when the length of its other two sides are known. For specific, step-by-step instructions on how to use this useful formula, usually given as a^2+b^2=c^2, where c^2 is equal to the length of the hypotenuse, watch this free video geometry lesson.