SOLUTION: 21000=12000(1+r/4)^36 solve for r

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Question 160536: 21000=12000(1+r/4)^36 solve for r
Answer by Fombitz(13823) About Me  (Show Source):
You can put this solution on YOUR website!
21000=12000%281%2Br%2F4%29%5E36
21%2F12=%281%2Br%2F4%29%5E36
Take the 36th root of both sides(when we do this we'll have both positive and negative solution).
We'll add that at the end.
%2821%2F12%29%5E%281%2F36%29=%281%2Br%2F4%29
%2821%2F12%29%5E%281%2F36%29-1=r%2F4
r=4%28%2821%2F12%29%5E%281%2F36%29-1%29and
r=-4%28%2821%2F12%29%5E%281%2F36%29-1%29and
or approximately r=0.0627, -0.0627
.
.
.
Just in case, your equation looks like this,
21000=12000%28%281%2Br%29%2F4%29%5E36
21%2F12=%28%281%2Br%29%2F4%29%5E36
%2821%2F12%29%5E%281%2F36%29=%281%2Br%29%2F4
4%2821%2F12%29%5E%281%2F36%29=1%2Br
r=4%28%2821%2F12%29%5E%281%2F36%29%29-1
Then approximately,
r=3.063,-3.063