Question

How do you factor when "a" is greater than 1? Pls show work

Answer 1

For $ax^2+bx+c$
if a≠1 then
first seee if you can undsitribute a
ifyou can't
use the ac method

multiply a and c
find 2 numbers that add to b and multiply to get ac
split b into that
group
undistribute
undistribute


so

$4x^2-7x-15$
ac=4*-15=-60
what 2 numbers multiply to get -60 and add to get -7?
5 and -12
split b up into -12 and 5
$4x^2-12x+5x-15$
group
$(4x^2-12x)+(5x-15)$
undistribute
$4x(x-3)+5(x-3)$
undistribute
$(4x+5)(x-3)$