SOLUTION: Solve 81x^3+36x^2=-4x

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Question 135999:
Solve 81x^3+36x^2=-4x
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
81x^3+36x^2=-4x
81x^3+36x^2+4x=0
x(81x^2+36x+4)=0
x=0 answer
using the quadratic equation we get:x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x=(-36+-sqrt[36^2-4*81*4])/2*81
x=(-36+-sqrt[1296-1296])/162
x=(-36+-0)/162
x=-36/162
x=-2/9 or -.222222 answer.