SOLUTION: text book by holt pre-algebra page 297 please help in finding the radis of a circle with the giving measurement: A=pie cm2

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Question 113728: text book by holt pre-algebra page 297 please help in finding the radis of a circle with the giving measurement:
A=pie cm2

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a circle is A=pi%2Ar%5E2, so if you are given the area and need to determine the radius, you simply solve this equation for r, thus:

pi%2Ar%5E2=A
r%5E2=A%2Fpi Divide both sides by pi
r=sqrt%28A%2Fpi%29 Take the square root of both sides

Remember that, in general, when you take the square root of something you have to consider both the positive and negative square roots: 2%5E2=4 AND %28-2%29%5E2=4. However, in this case you can exclude the negative square root because you are trying to find a length measurement, and a negative number for a length measurement is absurd.

The other thing to consider when presenting your answer is that the Area was given in cm%5E2. Taking the square root of a quantity measured in cm%5E2 means that your result will be in cm.

Hope this helps,
John