(y+4)-(y-1)=6; (13x-15)-(9+6x)=-3; 1,6x-(x-2,8)=(0,2x+1,5)-0,7
У+4-у+1=6у 5=6у у=5÷6 у=5/6 13х-15-9-6х=-3х 7х-24=-3х 7х+3х=24 10х=24 х=24÷10 х=2.4 1.6х-х+2.8=0.2х+1.5-0.7 0.6х+2.8=0.2х+0.8 0.6х-0.2х=0.8-2.8 0.4х=-2 х=-2÷0.4 х=-5