2(x+1.2)=6.4-0.4x+1.2=(6.4-0.4)/2x=(6.4-0.4)/2-1.2得x=1.8
去括号6.4-2X-2.4=0.4化简4-2X=0.4两边同除以2.2-X=0.2移向2-0.2=XX=1.8
先去括号6.4-2X-2.4=0.4移项2X=4-0.42X=3.6X=1.8
6.4-2x-2.4=0.44-2x=0.42x=4-0.42x=3.6x=1.8
2(x+1.2)=6 x+1.2=3 x=1.8