SOLUTION: solve the equation 3x+15=x^3+5x^2 algebraically for all values of x

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Question 392824: solve the equation 3x+15=x^3+5x^2 algebraically for all values of x
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x:
3x%2B15+=+x%5E3%2B5x%5E2 Reformat to look like:
x%5E3%2B5x%5E2-3x-15+=+0 Factor.
%28x%5E2-3%29%28x%2B5%29+=+0 Apply the zero product rule.
x%5E2-3+=+0 or x%2B5+=+0 so...
x%5E2+=3 then x+=+3 and x+=+-3 also...
x%2B5+=+0 then x+=+-5 so...The values of x are:
x+=+3, x+=+-3, x+=+-5