8x+2(3x-3)=30所以8x+2×3x-2×3=308x+6x-6=3014x=36x=36/14=18/7
8x+2(3x-3)=308x+6x-6=3014x-6+6=30+614x=36x=除不尽
8x+2(3x-3)=30 8x+6x-6=30 14x=36 x=36/14 约分就好
14x-6=30得x=18/7
8x+6x-6=3014x=36x=18/7