Question

Find the area: to the nearest whole number

Answer 1

The area of the composite area is 400 square millimeters.

Explanation:

The area of the composite figure (
`A`), in square millimeters, is found by multiplying the area of the equivalent rectangle, in which a semicircle of the original rectangle is move to the opposite side of the figure, so that quantity of area is conserved:

`A = w\cdot h` (1)

Where:

`w` - Width, in millimeters.

`h` - Height, in millimeters.

If we know that
`h = w = 20\,mm`, the area of the composite figure is:

`A = (20\,mm)\cdot (20\,mm)`

`A = 400\,mm^(2)`

The area of the composite area is 400 square millimeters.