Question

Make r the subject of the formula: V=pier^2h

Answer 1

If you mean π. Then, all that will be ;
V=πr²h
 First of all, you have to divide the both the sides by πh. You have to do this because the relationship between r and those two characters is multiplication. The opposite of multiplication is division. Anyway;
V/πh=πr²h/πh
V/πh=r²
  Next you have to take the square root of both sides. This is done to cancel the square. Anyway;
√V/πh=√r²
 The square root cancels the ². Anyway, you will be left with;
√V/πh=r
  So;
r=√V/πh.  
   Hope i helped. Have a nice day.

Answer 2

V = πr²h
Divide by h
V/h = πr²
Divide by π
V/πh = r²
Square Root
√<u />(V/πh) = r
r = √(V/πh)
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