SOLUTION: Please help me solve this problem: {{{x^3-2x^2-7x-4=0}}}

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Question 236937: Please help me solve this problem:
x%5E3-2x%5E2-7x-4=0
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E3-2x%5E2-7x-4=0 can be solved as follows:

divide x%5E3-2x%5E2-7x-4=0 by x-4 to get:

%28x-4%29+%2A+x%5E2+%2B+2x+%2B+1+=+0

factor x%5E2+%2B+2x+%2B+1 to get:

%28x-4%29+%2A+%28x%2B1%29+%2A+%28x%2B1%29+=+0

x = 4 or x = -1

I looked at the original equation and figured that if there was a way to divide (x-?) into it, then the ? had to be either 4 or a factor of 4 because that would make the division come out even.

I tried (x-2) into x^3 - 2x^2 - 7x - 4 but that didn't work.

I then saw that (x-4) might work and tried it.

It did.