Pythagorean Theorem again

another explanation:

The Pythagorean Theorem

The Pythagorean theorem, an important mathematical principle, uses right triangles. A right triangle is a triangle which has one right or 90° angle. The side opposite the 90° angle is called the hypotenuse .

The Pythagorean theorem states that for any right triangle c ² = a ² + b ² , where c is the length of the hypotenuse and a and b are the lengths of its sides (see Fig. 9-23 ) .

Fig. 9-23.

Finding the Hypotenuse

If you need to find the hypotenuse of a right triangle, use c = .

Finding the Sides of a Right Triangle

If you need to find the length of one side of a right triangle, use a = or b = .