Question 1149306: Hello, what are the steps to solving this math question:
Factor completely:
9x^2 + 9x -28 Found 2 solutions by Alan3354, ikleyn:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! Factor completely:
9x^2 + 9x -28
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Use trial and error.
It's (ax + c)*(bx + d)
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It'll be either
(x + c)*(9x + d) or
(3x + c)*(3x + d)
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c*d = -28 so the signs are different.
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The coefficient of x is odd, so either ad is odd and bc is even, or v.v.
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It's gets easier with practice.
If I can not guess factoring in 5 seconds, I use the quadratic formula to find the roots
of the associated quadratic equation and
As soon as I know the roots, the factoring form is ,
where coefficient "a" is the leading coefficient at x^2 in the original polynomial.
Doing this way, I save my brain from unnecessary job.
