factor the polynomial 3x^2+3x-6

2 answers

The answer should be 3(x - 2)(x + 1).

GCF is 3

Factor out 3.

3(x^2 - x - 2)

Numbers that add up to -1 and -2 are -2 and 1.

3(x - 2)(x + 1)

I hope this helps! :)
3x^2 + 3x - 6 = 0

A*C = 3*(-6) = -18 = -3*6
Choose the pair of factors whose sum = B = +3: -3, and 6.

3x^2 + (-3x+6x) - 6 = 0
Form two factorable binomials:
(3x^2-3x) + (6x-6) = 0
3x(x-1) + 6(x-1) = 0
(x-1)(3x+6) = 0
(x-1)*3(x+2) = 0

x-1 = 0
X = 1

3(x+2) = 0
Divide by 3:
x+2 = 0
X = -2

Solution set: X = -2, and 1.

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