2(x²-3)=(x-2)(2x+1)
2x²-6=2x²+x-4x-2
2x²-2x²-x+4x=-2+6
3x=4
x= 4/3
yz - 13yd + 78d - 6z = (yz - 6z) - (13yd - 78d) = z(y - 6) - 13d(y - 6) =
= (y - 6)(z - 13d)
<span>1.2с-0.3с+5=(1,2-0,3)с+5=0,9с+5</span>