How do you determine the area of a circle? could you give an example ?

If a circle has radius 5, its area will be pi multiplied by 5^2

Therefore the area is approximately 78.54 units^2

This polygon has 4 sides
180(4-2) = 180(2) = 360 degree
80+90+2x + 3x = 360
170+5x = 360
5x = 190
x= 38
measure of angle t is 2(38)= 76
the answer is c. trust me
hope this !