x/3+x/6=1|*6 2x+x=6 3x=6 x=2 y/3-y/2=-7|*6 2y-3y=-42 y=42 y/2-y/7=5|*14 7y-2y=70 y=14 z/5-z/10=1|*10 2z-z=10 z=10