SOLUTION: The sum of the circumference of two different circles is 40p and the sum of their areas is 364p cm^2. Calculate the radius of the two circles.

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Question 1141006: The sum of the circumference of two different circles is 40p and the sum of their areas is 364p cm^2. Calculate the radius of the two circles.
Found 2 solutions by josmiceli, MathTherapy:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add the circumferences
+C%5B1%5D+%2B+C%5B2%5D+=+40p+
+2pi%2Ar%5B1%5D+%2B+2pi%2Ar%5B2%5D+=+40p+
+r%5B1%5D+%2B+r%5B2%5D+=+%28+40pi+%29+%2F+%28+2pi+%29+
+r%5B1%5D+%2B+r%5B2%5D+=+20+
+r%5B2%5D+=+20+-+r%5B1%5D+
----------------------------
Add the areas
+A%5B1%5D+%2B+A%5B2%5D+=+364p+
+pi%2Ar%5B1%5D%5E2+%2B+pi%2Ar%5B2%5D%5E2+=+364p+

+r%5B1%5D%5E2+%2B+400+-+40r%5B1%5D+%2B+r%5B1%5D%5E2+=+364p+
+2r%5B1%5D%5E2+-+40r%5B1%5D+%2B+400+-+364p+=+0+
+r%5B1%5D%5E2+-+20r%5B1%5D+%2B+200+-+182p+=+0+
--------------------------------------------
+r%5B1%5D+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

+r%5B1%5D+=+%28+20+%2B-+sqrt%28+400+%2B+728p+-+800+%29%29%2F2+
+r%5B1%5D+=+%28+20+%2B+sqrt%28+728p+-+400+%29%29+%2F+2+
and
+r%5B2%5D+=+40%2F2+-+%28+20+%2B-sqrt%28+728p+-+400+%29%29+%2F+2+
+r%5B2%5D+=+%28+20+-+sqrt%28+728p+-+400+%29%29+%2F+2+
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check the math & definitely get another opinion.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of the circumference of two different circles is 40p and the sum of their areas is 364p cm^2. Calculate the radius of the two circles.
If you NEED a correct answer, then you have to submit the correct problem, worded exactly as given. Did you really expect to get a correct answer

by just submitting the problem without even checking to see if itw's correctly copied? And what about us who're trying to help you? Do we need 

to decipher your math problem, plus solve it for you? I think NOT!! BTW, I have a good idea what the actual problem states, and also its solution.

Would I care to share it with you? NEGATIVE!!!