How do you make Pythagoras theorem model?

First construct a right angle triangle with dimensions of:

base = 3 units, height = 4 units and hypotenuse = 5 units

Then construct 3 exterior squares on each of the sides with the given dimensions.

Sub-divide these squares into smaller squares so that the base has 9, the height has 16 and the hypotenuse has 25

Pythagoras' theorem says: base2+height2 = hypotenuse2

Congratulations, your visual model proves that this is true.