Stage: 3 Challenge Level: 
Turn the triangle of area 0.5bh into a rectangle of dimensions b by 0.5h using the midpoints of edges. The square has side length given by s2 = 0.5bh. There is a lot to explain here about why the pieces fit exactly as shown.
Generalising. smartphone. Circles. Games. Area. Interactivities. Compound transformations. Small software. Visualising. Pythagoras' theorem.
Published February 2002.
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