(2/3-1,2)-(-1,8+2/3) по действиям

1) 2/3-1,2=2/3-1 2/10=2/3-6/5=10/15-18/15=-8/15 2) -1,8+2/3=-1 8/10+2/3=-9/5+2/3=-27/10+10/15=-17/15 3)-8/15-(-17/15)=-8/15+17/15=9/15=3/5