If a right circular cylinder has a volume of 144pi and a height of 9, what is the area of its base? is it: a. 8 pi b. 12 pi c. 16 pi d. 25 pi...

The formula for volume of a cylinder
is...

V = r^2 * h * pi

Given
that the volume is 144pi and the height is 9, you can write the following equation using
substitution

144(pi) =
9r^2(pi)

Divide both sides by
pi.

144 = 9r^2

Divide by sides
by 9.

16 = r^2

Square root
both sides.

4 = r

Since the
area of the base of a cylinder is a circle, the formula
is...

A = pi * r^2

Substitute
4 in for the variable r.

A = pi *
16

Your answer is 16pi (option c)