Question

If a circle has a circumference of C, what is the area of the circle in terms of C?

A=πC

A=C24π

A=2Cπ

A=2C2

Answer 1

The area is A=pi*r^2, and the Circumference is C=2*pi*r

the ansers have pi in them, so solve both Area and Circumference for the radius r

Answer 2

then you can set them equal to each other since they will both equal r

Answer 3

\[r = \sqrt{\frac{ A }{ \pi }}\]

and
\[r = \frac{ C }{ 2\pi }\]

Answer 4

Set the two right sides equal and solve for A

Answer 5

k

Answer 6

Is their a correct choice? I think we need\[A=(C ^{2})/(4\pi)\]Am I missing something??

Answer 7

Probably the 2nd option has a typo.