How do you factor $y=2x^2+11x+12$ ?

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Answer 1 · 2016-08-02T12:26:48

$y = (2x + 3)(x+4)$

Find factors of 2 and 12 which add together to give 11.

find the cross products and add. There is some trial and error.

$" 2 3" rArr 1xx3 = 3$
$" 1 4" rArr 2xx4 = 8 " "3+8=11$

The signs are the same they are both positive.

$y = (2x + 3)(x+4)$

Answer 2 · 2016-08-02T12:36:39

$(x+4)(2x+3)$

First, let's find the zeros of the function y by solving the equation:

$2x^2+11x+12=0$

$x=(-11+-sqrt(11^2-4*2*12))/(2*2)$

$x=(-11+-sqrt(121-96))/4$

$x=(-11+-sqrt(25))/4$

$x=(-11+-5)/4$

$x_1=-4 and x_2=-3/2$

You can factor a trynomial:

$y=ax^2+bx+c=a(x-x_1)(x-x_2)$

and have:

$2x^2+11x+12=2(x+4)(x+3/2)$

that's

$(x+4)(2x+3)$

How do you factor y=2x^2+11x+12y=2x^2+11x+12 ?