Question 1210579
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The area of a circle is 9π in². What is the circumference, in inches? Express your answer in terms of piπ.
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<pre>
Use the formula for the area of a circle

    {{{pi*r^2}}} = {{{9*pi}}}  in^2.


where  'r'  is the radius of the scuare.

From this equation

        {{{r^2}}} = 9,  r = {{{sqrt(9)}}} = 3.


Then the circumference of the circle is

    circumference = {{{2pi*r}}} = {{{2pi*3}}} = {{{6pi}}} inches.


<U>ANSWER</U>.  The circunference of the circle is  {{{6pi}}} inches.
</pre>

Solved.