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2 votes
The circumference of a circle is 19pi ft. What is the area, in square feet? Express your

answer in terms of pi.

2 Answers

1 vote

Answer:

Explanation:

Circumference is found in


C=2\pi r while area is
A=\pi r^2

Since we know the circumference value, we can plug it in and solve for r:

Since
C=2\pi r and
C=19\pi , then


19\pi=2\pi r and


(19\pi)/(2\pi)=r The pi's cancel out, leaving us with the fact that


r=(19)/(2)=9.5

We will use that now in the area formula:


A=\pi(9.5)^2 so

A = 90.25π

User IjzerenHein
by
6.5k points
3 votes

Answer:

A = 90.25 pi ft^2

Explanation:

The circumference is given by

C = 2 * pi* r

19pi = 2 * pi * r

Divide each side by 2pi

19pi/2pi = 2 * pi *r/2pi

9.5 = r

Now find the area

A = pi r^2

A = pi ( 9.5)^2

A = 90.25 pi ft^2

User Georgy Gobozov
by
7.7k points