-3(4х-0,6y)-(-x+2,8y)
-3(4x-0,6y)-(-x+2,8y)= -12x+1,8y+x-2,8y=-11x-y
-3(4х-0,6y)-(-x+2,8y)=-12x+1.8y+x-2.8y=-11x-y