The area of a triangle is always half that of a rectangle with the same height and width.

To find the area of a triangle, therefore, we multiply the width (or base) by the height, and then divide that by 2.

For example, in this right-angled triangle, the base measures 10 and the height measures 11.

So the area is:

10 x 11 = 110
110 ÷ 2 = 55 cm²

Try it out

What is the area of this triangle, which measures 16 cm along the base and 10 cm in height?

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