(2х+3)(3-2х)-(2х-5)²-10х=6х-4х²+9-6х-4х²+20х-25-10х=-8х²+10х-16
<span>(3x+y)^2+(3xy-1)^2-(3x-y)^2=
</span>((3x+y)+(3x-y))(<span>(3x+y)+<span>(3x-y))</span>+(3xy-1)^2=
</span>(6x)(<span>2y)+(3xy-1)^2=</span>(12xy)+(3xy)^2-<span>6xy+1=
</span>=(3xy)^2+<span>6xy+1=</span>(3xy+1)^2=(3xy+1)(3xy+1)
5х² + 15х = 0
5х (х + 3) = 0
Х1 = 0
Х2 = - 3
9х² + 18х = 0
9х (х + 2х) = 0
Х1 = 0
Х2 = - 2