8. What is the area of a circle whose diameter is 10?
A.10 pi
B.20 pi
C.25 pi
D. 100 pi

25 pi

Step-by-step explanation:

area of circle = pi (r)^2

radius = 10/2 = 5

5×5 = 25

25 pi

C

Step-by-step explanation:

The formula is pi(r＾2)

r=radius

=10/2

(2x + 16) + (x) = 180

step-by-step explanation:

given,

abcd is a quadrilateral inscribed in a circle

angle a is labeled x plus 16, (x + 16)

angle b is labeled x degrees, (x)

angle c is labeled 6x minus 4, (6x – 4)

angle d is labeled 2x plus 16, (2x + 16)

what equation can be used to solve for angle b?

we know that the sum of the opposite angles of a simple quadrilateral inscribed in a circle is 180 degrees.

angle b is opposite angle d

therefore, angle b + angle d = 180

(x) + (2x + 16) = 180 

same as (2x + 16) + (x) = 180