0.6（x-0.4）+3.8=1.2x+0.56

0.6（x-0.4）+3.8=1.2x+0.56
0.6（x-0.4）+3.8=1.2x+0.56

0.6（x-0.4）+3.8=1.2x+0.56
0.6x－0.24＋3.8＝1.2x＋0.56
0.6x＝3.8－0.56－0.24
0.6x＝3
x＝5

0.6(x-0.4)+3.8=1.2x+0.56
乘开 0.6x-0.24+3.8=1.2x+0.56
移项 -0.24+3.8-0.56=1.2x-0.6x
化简 3=0.6x
结果 x=5