Stage: 3 Challenge Level: 
Imagine having a pencil, ruler, protractor and compass and being asked to draw the triangle below.
Can you explain why it is an impossible triangle to construct?
Interactivities. Mathematical reasoning & proof. Angle properties of shapes. Reflections. Cubes. Generalising. Visualising. Short problems. Ruler & protractor constructions. Equilateral triangles.
Published June 2007.
Copyright © 2007. University of Cambridge. All rights reserved.
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