SOLUTION: Solve {{{x+2=root(3,12x+2)}}}

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Question 135472: Solve x%2B2=root%283%2C12x%2B2%29
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%2B2=root%283%2C12x%2B2%29 Start with the given equation


%28x%2B2%29%5E3=12x%2B2 Cube both sides


x%5E3%2B6x%5E2%2B12x%2B8=12x%2B2 Expand the left side



x%5E3%2B6x%5E2%2B12x%2B8-12x-2=0 Subtract 12x from both sides. Subtract 2 from both sides.


x%5E3%2B6x%5E2%2B6=0 Combine like terms


So from a graphing calculator, we find that the solution to x%5E3%2B6x%5E2%2B6=0 is x=-6.15821