1) ...=х^2+4х+3х+12=х^2+7х+12
2) ...=х^2-6х-2х+12=х^2-8х+12
3) ...=х^2-3х+5х-15=х^2+2х-15
4) ...=х^2-2х-7х+14=х^2-9х+14
5) ...=2х^2-10х+х-5=2х^2-9х-5
6) ...=3х^2+2х-18х-12=3х^2-16х-12
7) ...=24х^2-32х+12х-16=24х^2-20х+12
8) ...=12х^2-21х-20х+35=12х^2-41х+35