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Age 14 to 16
Challenge Level

Can you draw a square  ABCD with BC on the base PR of the triangle and the vertex D on the side PQ using ruler and compasses?


Small square drawn in left-hand corner of the triangle


What happens to the point A as you enlarge the square? The interactivity may help. Move Q to specify your triangle, and then move D to enlarge the square.

How can you use this to help you draw the square you require?