SOLUTION: Factor 7x^2-14x-56 and factor 9x^2-336x+27

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Question 681613: Factor 7x^2-14x-56
and
factor 9x^2-336x+27
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Factor 7x^2-14x-56
First factor out the greatest common factor. In this case all three terms are divisible by 7.
7%28x%5E2-2x-8%29
Now we know that we have:
7(x+___)(x-___) Because the last term is negative.
We need to find to numbers that multiply to give -8 (the last term) but add to get -2 (the middle term)
-4*2 = -8 and -4+2=-2
highlight%287%28x%2B2%29%28x-4%29%29

I think the next one might be a type-0, so I will do it as you wrote it, then do it based on my experience of what the type-o might be.

factor 9x^2-336x+27
The all numbers are divisible by 3.
highlight%283%283x%5E2-112x%2B3%29%29
That's all you can do.

I think you meant:
factor 9x%5E2-36x%2B27
Everything is divisible by 9
9%28x%5E2-4x%2B3%29
-3*-1=3 and -3+-1=-4
highlight%289%28x-3%29%28x-1%29%29
Hope that helped. Happy Calculating.