SOLUTION: 4x^3+x^2-36x-9=0

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Question 318002: 4x^3+x^2-36x-9=0
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x???
4x%5E3%2Bx%5E2-36x-9+=+0 Factor by grouping.
%284x%5E3%2Bx%5E2%29-%2836x%2B9%29+=+0
x%5E2%284x%2B1%29-9%284x%2B1%29+=+0 Factor (4x+1)
%284x%2B1%29%28x%5E2-9%29+=+0 Factor the second binomial.
%284x%2B1%29%28x%2B3%29%28x-3%29+=+0 Apply the zero product rule.
4x%2B1+=+0 or x%2B3+=+0 or x-3+=+0 so...
x+=+-1%2F4
x+=+-3
x+=+3