Question

PLZZ IN NEED HELP!

Find the area of the shaded regions. Give your answer as a completely simplified exact value in terms of π (no approximations).

Answer 1

`18\pi\ cm^2`

Explanation:

step 1

Find the area of complete circle

The area of the circle is given by the formula

`A=\pi r^(2)`

we have

`r=9\ cm`

substitute

`A=\pi (9)^(2)`

`A=81\pi\ cm^2`

step 2

Find the area of the shaded region

we know that

The area of complete circle subtends a central angle of 360 degrees

so

using proportion

Find out the area of the shaded region if the central angle is equal to 80 degrees

`(81\pi)/(360^o)=(x)/(80^o)\\\\x=81\pi(80)/360\\\\x= 18\pi\ cm^2`