Question 1149306
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.