SOLUTION: What is the circumference of a circle if the area is {{{81pi}}}?

Question 319932: What is the circumference of a circle if the area is ?
Found 2 solutions by Edwin McCravy, stanbon:
Answer by Edwin McCravy(20055) (Show Source): You can put this solution on YOUR website!
What is the circumference of a circle if the area is ?

Use the Area formula to find the radius; then use that value for r in the circumference formula . Edwin

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
What is the circumference of a circle if the area is 81pi
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Area = pi*r^2
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Solve for "r":
pi*r^2 = 81pi
r^2 = 81
r = 9
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Circumference = 2*pi*r
C = 2*pi*9
C = 18*pi
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Cheers,
Stan H.
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