Proof of Pythagoras Theorem

Pythagoras Water Wheel Demo

Watch the YouTube Video and observe how the water in the big square (c2) fills exactly the small squares (a2 + b2) and vice-versa.

Try It!

The blue points on the triangle allow you to resize the triangle. Use the 2 red points on the ruler to move and rotate the ruler.

In this activity, you can measure the 3 lengths of the triangle to explore the relationship between the 3 sides.

Proof of Pythagoras' Theorem 

Proof of Pythagoras' Theorem II

Use the applet below to explore the original proof by Euclid. Note that the blue and red area remains invariant as shearing and rotating does not change the area of a shape.

Proof of Pythagoras' Theorem III

Use the applet below to explore a proof of Pythagoras' Theorem.