SOLUTION: solve for x showing your work? 5x^3+45x=2x^2+18

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Question 1095165: solve for x showing your work?
5x^3+45x=2x^2+18
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
5x%5E3+%2B+45x = 2x%5E2%2B18  ====>

5x%2A%28x%5E2%2B9%29 = 2%2A%28x%5E2%2B9%29    ====>

5x%2A%28x%5E2%2B9%29 - 2%2A%28x%5E2%2B9%29  = 0  ====>  

%285x-2%29%2A%28x%5E2%2B9%29 = 0  ====>


There is one real root  x%5B1%5D = 2%2F5  and two complex roots  x%5B2%5D = 3i,  x%5B3%5D = -3i.

Solved.