SOLUTION: For what nonzero value of the radius is the circumference of a circle numerically equal to its area?

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Question 164142: For what nonzero value of the radius is the circumference of a circle numerically equal to its area?
Found 2 solutions by Alan3354, Edwin McCravy:
Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
For what nonzero value of the radius is the circumference of a circle numerically equal to its area?
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Good question, I never thought of that.
Area = PI*r^2 = 2PIr = circumference
PI*r^2 = 2PIr
Divide by PI*r
r = 2
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Area = 4PI
Circum = 4PI

Answer by Edwin McCravy(20054)   (Show Source): You can put this solution on YOUR website!
Edwin's solution:
For what nonzero value of the radius is the circumference of a circle numerically equal to its area?




If we want , then



Divide both sides by :



Cancel the 's





Get 0 on the right by adding  to both sides:



Factor out  on the left:



Use the zero-factor property:



Answer: the nonzero value of  is .

Edwin
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