Question 5372: I'm sorry, I need help again.
What is the radius of a circle whose area is 154 square centimeters?
A=pi r(squared) for pi they are using 22/7 if I am right that is 3.14?
154=3.14 r(squared)
This is as far as I can get because I can not remember how to do the squared.
After this I am going to bed. My brain is fried trying to fiqure all these out and trying to explain them to him in the process.
Answer by rapaljer(4671)   (Show Source):
You can put this solution on YOUR website! You are right to say,  , where pi is approximately 3.14 or also approximately  . I checked out the problem and because the area is given as 154 square centimeters, they used  as the approximation for pi.
To solve for  , you can divide both sides by . Since this will get ugly looking, you might want instead to MULTIPLY both sides of the equation by the reciprocal of , which is  .
It looks like this:
Amazingly enough, the 22 in the denominator on the left side of the equation just happens to divide evenly into 154, and it goes 7 times. So you will have
So if  , then
r= 7 or r= -7. The radius cannot be negative, so r= 7 centimeters.
R^2 at SCC
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