Stage: 3 Challenge Level: 
Hint
The information about perpendicular is important
Try to draw the net of each portion, labelling the edges and their lengths.
Prisms. Mathematical reasoning & proof. Nets. Interactivities. Cubes. 2D representations of 3D shapes. Generalising. Pythagoras' theorem. Working systematically. Visualising.
Published February 2003.
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