(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=6у5=6уу=5÷6у=5/613х-15-9-6х=-3х7х-24=-3х7х+3х=2410х=24х=24÷10х=2.41.6х-х+2.8=0.2х+1.5-0.70.6х+2.8=0.2х+0.80.6х-0.2х=0.8-2.80.4х=-2х=-2÷0.4х=-5