The classic Pythagorean Theorem states the sum of the squares on the legs of a triangle is equivalent to the square on the hypotenuse or [math]a^2 + b^2 = c^2[/math].

This applet illustrates 7 additional proofs of the theorem using other regular polygons, i.e., the polygon on the sides can be any regular polygon. Here we can see polygons with 3 - 10 sides. Also, it can be shown the shapes using the sides can be semicircle and other regular shapes.