5 / 6 (3х-у)-(1,5х+1 / 6у)
5:6*(3x-y)-(1,5x+1:6y) 5:6=5/6 3x*5/6=15/6x=2,5x y*5/6=5/6y 2,5x-5/6y-1,5x-1/6y = x-y