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

Answer:

$18\pi\ cm^2$

Step-by-step 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

$\frac{81\pi}{360^o}=\frac{x}{80^o}\\\\x=81\pi(80)/360\\\\x= 18\pi\ cm^2$