解方程(1)x÷15+0.4=x÷12-0.1 &
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/21 16:23:52
解方程 (1)x÷15+0.4=x÷12-0.1 | (2)150.5-4x+0.5x=7. |
(1)x÷15+0.4=x÷12-0.1,
1
15x+0.4=
1
12x-0.1,
1
15x+0.4-
1
15x=
1
12x-0.1-
1
15x,
0.4+0.1=
1
60x-0.1+0.1,
0.5×60=
1
60x×60,
x=30;
(2)150.5-4x+0.5x=7,
150.5-3.5x=7,
150.5-3.5x+3.5x=7+3.5x,
150.5-7=7+3.5x-7,
143.5÷3.5=3.5x÷3.5,
x=41.
1
15x+0.4=
1
12x-0.1,
1
15x+0.4-
1
15x=
1
12x-0.1-
1
15x,
0.4+0.1=
1
60x-0.1+0.1,
0.5×60=
1
60x×60,
x=30;
(2)150.5-4x+0.5x=7,
150.5-3.5x=7,
150.5-3.5x+3.5x=7+3.5x,
150.5-7=7+3.5x-7,
143.5÷3.5=3.5x÷3.5,
x=41.