An interactive applet and associated web page that demonstrates a graphical proof of Pythagoras' Theorem. The applet shows a right triangle that is replicated and then moved around to demonstrate the relationship between the sides. It can can be stepped through slowly to allow classroom discussion, or let to run as a movie. Useful for students who like to see things graphically as opposed to symbolically.

Applet can be enlarged to full screen size for use with a classroom projector. After use in the classroom, student can access it again from any web browser at home or in the library with no login required.

This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.