Question

How do i answer this question please

Answer 1

`a=113mm^(2)`

Explanation:

shaded area = Semicircle Area - Area of the Inside Circle

1. Area of the Inside Circle:

`d=24/2=12mm\\r=12/2=6mm`

`a=\pi r^(2) =\pi (6)^(2) =36\pi`

2. Semicircle area:

`r=24/2=12mm`

`a=(\pi r^(2) )/(2)=(\pi (12)^(2) )/(2) =(144\pi )/(2) =72\pi`

3. Shaded area:

`a=(72-36)\pi =36\pi`

`36\pi` ≈
`113.097`

3 significant figures: 113 mm2

Hope this helps

Answer 2

Explanation:

The RADIUS of the white circle is 6 mm (because diameter is 12mm)

area of white circle = pi r^2 = pi(6^2) = 113.097 mm^2

The SEMI circle area is radius 12 mm

area is 1/2 of an entire circle of radius 12 mm = 1/2 * pi r^2 =

1/2 * pi * 12^2 = 226.19 mm^2

subtract the white circle area to get shaded area = 113 mm^2