Question 890552: solve for x (the answer is about 9.05)
x^3-9x^2-4=0
so far I did this but I don't know if this is right
x(x^2-9x+20.25)=4+20.25x ;Move 4 to other side,factor out x,and complete square
x(x-4.5)^2=4+20.25x I got stuck here
Answer by josgarithmetic(39616)   (Show Source):
You can put this solution on YOUR website! One would imagine you want or should want to use Rational Roots Theorem and try to factor the polynomial. Use synthetic division to check for possible roots of -1,-2,-4,1,2,4.
A quick check using the graphing finding feature of google indicates or suggests ONLY one real root, and it is near, slightly above x=9. The equation does not have any rational roots. Solving for x using the usual number properties will not be too helpful. Try approximating for x numerically.
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