3(2x-4)=9解: 6x-12=9 6x=9+12 6x=21 x=7/2 望采纳
两边同时除以3得2x-4=32x=7得x=3.5
9=6x-12 6x=9+12 6x=21 x=21/6 x=3.5
6X—12=9 6X=21 X=3.5
6x-12=9 6x=21 x=2/7