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Shear Magic

Age 11 to 14 Challenge Level:

All these triangles have a base of 1 unit and a height of 2 units. We could call them a "family" of triangles.

1 by 2 right angled triangle sheared 1 by 2 right angled triangle more sheared 1 by 2 right angled triangle very sheared 1 by 2 right angled triangle

What are their areas? What do you notice?

Can you generalise to other "families" of triangles?

You may like to use the interactivity below to investigate more triangles

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