SOLUTION: What is the radius of a circle if the area is 3 times greater than the circumference?

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Question 703727: What is the radius of a circle if the area is 3 times greater than the circumference?
Answer by mouk(232) About Me  (Show Source):
You can put this solution on YOUR website!
Let the radius be denoted by +r+ then:
+area=pi%2Ar%5E2+
+circumference=2pi%2Ar+

area is 3 times greater than the circumference? So
+area+=+3%2Acircumference+
+pi%2Ar%5E2+=+3%2A2pi%2Ar+

We can cancel a factor of +pi+ giving:
+r%5E2+=+6r+
+r%5E2+-+6r+=+0+
+r%28r-6%29+=+0+
Giving two solutions: r=0 or r=6 of which only r=6 is relevant to problem.