Question

Find the area of the shaded portion below.

Answer 1

Explanation:

The shaded area is a trapezoid minus the area of half a circle.

T=h(b1+b2)/2

T=40(50+80)/2

T=2600cm^2

Now the area of the half circle

C=(pi r^2)/2

C=(400pi)/2

C=200pi

So the shaded area is

A=2600-200pi

A=1972 (rounded to nearest 1)

Answer 2

Explanation:

the area of the half-circle:

πr² /2= 3.14* 20² /2= 3.14 * 400 /2 =1256/2=628cm²

50*80/2=2000cm²

Shaded area:

2000-628=1372cm²