Question 182224
Find all factors of x^2+x-12
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Having the coeff of x^2 = 1 makes it simpler.
Any factors will be
(x +- ?)*(x +- ?)
Only the two numbers that multipy to be -12 are a mystery.
There are a few possibilities:
1 & 12
2 & 6
3 & 4
That's all
Since it's -12, one will be negative and one positive.
Since there's 1x, the positive number will be 1 more than the negative number.
Also, since there's 1x, the 2 numbers differ by 1.
Only 3 & 4 fit.
So it's +4 and -3.
(x+4)*(x-3)