SOLUTION: The area of a circle is calculated using the following equation: A=(pi)r(squared). (I couldn't find the symbols for either pi or squared.) Anyhow, the equation needs to be re

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Question 175941: The area of a circle is calculated using the following equation:
A=(pi)r(squared). (I couldn't find the symbols for either pi or squared.)
Anyhow, the equation needs to be rewritten. If the diameter is half the radius, how can I rewrite the equation, A=(pi)r(squared)?
Is (pi)d(squared) over 4 the correct answer? If so what is the steps to achieving that answer?
Note: A stands for the area of a circle, r stands for radius, and d is for diameter.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Note: diameter = 2*radius. So d=2r which means that r=d%2F2

A=pi%2Ar%5E2 Start with the given equation.


A=pi%2A%28d%2F2%29%5E2 Plug in r=d%2F2


A=pi%2A%28d%5E2%2F4%29 Square d%2F2 to get %28d%2F2%29%5E2=%28d%2F2%29%28d%2F2%29=d%5E2%2F4