Question 426383
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how do i solve this problem??
 "if a circle has an area of 81 pi inches squared what is the circumference. leave your answer in terms of pi."
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        The solution in the post by @mananth is incorrect.

        I came to bring a correct solution.



<pre>
{{{pi*r^2}}} = {{{81*pi}}},  the area

{{{r^2}}} = {{{81*pi/pi}}}

{{{r^2}}} = 81

r = {{{sqrt(81)}}} = 9

{{{2pi*r}}} = circumference

{{{2*9*pi}}} = circumference

{{{18*pi}}} = circumference.    <U>ANSWER</U>
</pre>

Solved correctly.