60x=80x-80 两边同加80: 60x+80=80x 两边同减60x 20x=80 两边同除以20 x=4
解:60x=80x-80 60x+80=80x-80+80 60x+80=80x 60x+80-6x=80x-60x 80=20x 20x÷20=80÷20 x=4
60x=80x-80 80= 20x x=4