Answer:

Step-by-step explanation:
we know that
The area of the shaded region is equal to the area of the sector minus the area of the triangle
step 1
Find the area of the circle
the area of the circle is equal to

we have

substitute


step 2
Find the area of the sector
we know that
The area of the circle subtends a central angle of 360 degrees
so
by proportion find out the area of a sector by a central angle of 72 degrees

step 3
Find the area of triangle
The area of the triangle is equal to

step 4
Find the area of the shaded region
Subtract the area of the triangle from the area of the sector

180 degrees is the correct answer.
Opposites are the same difference from zero!
The answer is b hope it helped
Answer:
C
Step-by-step explanation:
When we write an equation, we look for something like is or equals
A.twice as much as a number 2x
B.12 less than a number x-12
C.half of a number is 15 1/2x =15
D.the difference of 20 and a number? 20-x
A,B, and D are expressions