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Proof Without Words: Pythagorean Theorem

Math Content:

Why is c2 = a2 + b2? Watch a dynamic, geometric "proof without words" of the Pythagorean Theorem. Can you explain the proof?

How to Use

Use the red points on the sliders to adjust the lengths of the sides of the triangle.


  • The buttons are meant to be used sequentially, and will appear in the order in which they are meant to be pressed.
    • Be sure to allow all movements to cease before pressing another button, as this will affect the performance of the sketchpad.
  • The Reset button will allow you to start over.


  • Why does this proof work? Construct a proof.
  • Do some research online to find other ways to prove the Pythagorean Theorem.


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6.5 Understanding the Pythagorean Relationship

Provide a proof without words for the Pythagorean Theorem.
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Pythagorean Review


Review and explore the Pythagorean Theorem.