Question 320903: (3c-2)^3-50=100
so far I have...
(3c-2)^3=150
3c^3 -8=150
3c^3=158
Answer by toidayma(44)   (Show Source):
You can put this solution on YOUR website! Well, you have a problem in expanding the (3c-2)^3 = 3c^3 - 2^3. It is not correct. If you really want to expand it, it has to follow the formula: (x+y)^3 = x^3 + 3x^2y + 3xy^2 + y^3. But there is an easier way to solve this:
(3c - 2)^3 = 150
<-> (3c-2) = 150^(1/3)
<-> 3c = 150^(1/3) + 2
<-> c = (150^(1/3) + 2)/3
I think this solution is much better.
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