How do you write 4x^2+2x-12 in factored form?

1 Answer
Sep 16, 2015

4x^2+2x-12
color(white)("XXXXXX")=color(green)(2)color(red)((2x+3))color(blue)((x-2))

Explanation:

Extract the obvious constant factor of 2 to simplify

color(green)(2)color(orange)((2x^2+x-6))

Factoring
by looking for integer factors a and b of 2
and integer factors c and d of (-6)
such that
(ad+bc)x = 1x

The only integer factors of 2 are 1xx2

Integer factors of (-6) are {(1xx-6),(2xx-3)(-1xx6),(-3xx2)}

Checking the four possible combinations, we find:
color(orange)((2x^2+x-6))=color(red)((2x+3))color(blue)((x-2))

So 4x^2+2x-12
color(white)("XXX")=color(green)(2)color(orange)((2x^2+x-6))
color(white)("XXX")=color(green)(2)color(red)((2x+3))color(blue)((x-2))