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Tessellating Triangles

Age 7 to 11 Challenge Level:

Equilateral triangles have three sides the same length and three angles the same. Can you make them fit together to cover the paper without any gaps between them? This is called 'tessellating'. red triangle.

What about triangles with two equal sides? These are isosceles triangles.

lilac isosceles triangle. pink isosceles triangle.

Can you tessellate all isosceles triangles?

Now try with right angled triangles. These have one right angle or 90 degree angle.

A blue, red and green right-angled triangle.

Some triangles have sides that are all different. Can you tessellate these?

A green and blue triangle.

Could you tessellate any triangle?