解:解方程, 此方程的解为x = 7/10,【即x = 0.7】
4 - 5x = x - 0.2
x + 5x = 4 + 0.2
6x = 4 + 2/10
6x = 40/10 + 2/10
6x = 42/10
6x = 21/5
x = 21/5 ÷ 6
x = 21/5 × 1/6
x = 7/10
∴x = 0.7
答:此方程的解为x = 7/10,【即x = 0.7】
解:由已知5x - 5x*0.2 = 4/5,所以5x - x = 4/5,合并可得4x = 4/5,解得x = 1/5 ;综上所述,原方程的解为 x = 1/5 。
等式两边同时加上5x
即4=6x-0.2
再同时加上0.2
4.2=6x
x=0.7
解得x=0.7
4-5X=X-0.2
4+0.2=X+5X
4.2=6X
X=4.2÷6=0.7
首先移项,得6x=4.2
两边同时除以6,得x=0.7