Question 882291
First use the circumference formula {{{C = 2*pi*r}}} to find the radius.



{{{C = 2*pi*r}}}


{{{8pi = 2*pi*r}}} Plug in the given circumference {{{C = 8pi}}}


{{{(8pi)/(red(2)) = (2*pi*r)/(red(2))}}} Divide both sides by 2.


{{{(cross(8)^4*pi)/(cross(2)) = (cross(2)*pi*r)/(cross(2))}}}


{{{4pi = pi*r}}}


{{{(4pi)/(red(pi)) = (pi*r)/(red(pi))}}} Divide both sides by {{{pi}}}.


{{{(4*cross(pi))/(cross(pi)) = (cross(pi)*r)/(cross(pi))}}}


{{{4 = r}}}


{{{r = 4}}}


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The radius is {{{r = 4}}}. Use this to find the area


{{{A = pi*r^2}}}


{{{A = pi*4^2}}}


{{{A = 16pi}}} Exact Area (in terms of {{{pi}}})