Golden -> Java Sketches

An online activity to help students reason visually about the Pythagorean Theorem.

John Golden's: homepage and javasketchpad page .

This proof features 8 copies of a right triangle, arranged to make two large squares apparently of equal area. It was found on a Chinese tablet over 2000 years ago. Note there's one spot in the animation where a triangle leaps out of the square. I don't know why either!

  1. Where are a, b and c in this picture?
  2. How does this picture illustrate the Pythagorean Theorem?
  3. What mathematical information does the animation show?
  4. Write algebraically what the left side of the picture demonstrates.
  5. Write algebraically what the right side of the picture demonstrates.
  6. Can your answers to (4) and (5) be put together to make an algebraic proof?

The original Sketchpad file: pythagoreanchin.gsp

This page uses JavaSketchpad, a World-Wide-Web component of The Geometer's Sketchpad. Copyright © 1990-2001 by KCP Technologies, Inc. Licensed only for non-commercial use.

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