SOLUTION: Is there a quick method you know to factor things out quickly?
like x^2-4x-12
How do I know just from quickly looking at it what it's gonna be? I've seen other people do thi
Question 1005948: Is there a quick method you know to factor things out quickly?
like x^2-4x-12
How do I know just from quickly looking at it what it's gonna be? I've seen other people do this like how to set up the signs and know wat goes where. I think there is an easy way to solve these problems that I don't know about. I have to make a lot of guesses and then foil everything out until I get it right.
Thanks Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website! Is there a quick method you know to factor things out quickly?
like x^2-4x-12
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It's trial and error.
(ax + b)*(cx + d) = x^2-4x-12
There are things to notice, tho.
The -12 --> b & d have different signs, one is + and one is negative.
The -4x --> the negative term is larger.
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It's not too hard when the coefficient of the x^2 = 1.
a = c = 1
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b*d = -12
b + d = -4
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You find a combo of b & d that work.
There are not many pairs of integers with a product of 12.
Find the pair that differ by 4.
1*12 NG
2*6
3*4 NG