# Solving Polynomial Equations

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• Oct 1st 2011, 09:01 AM
Dragon08
Solving Polynomial Equations
The passenger section of a train has width 2x-7, length 2x+3, and height x-2, with all dimensions in metres. Solve a polynomial equation to determine the dimensions of the section of the train if the volume is 117 m^3.

I tried this and I got the expanded equation 4x^3-16x^2-5x-75. When I tried solving it, it was unfactorable, but the answer at the back has whole number answers.
Can somebody help me please?
• Oct 1st 2011, 09:19 AM
Quacky
Re: Solving Polynomial Equations
Agreed with $4x^3-16x^2-5x-75=0$
I think there is a real, integer root. Test the factors of 75: x=1, x=3, x=5, etc until you find it.