解:(1)x-
![](http://thumb.1010pic.com/pic5/latex/335.png)
x=21,
![](http://thumb.1010pic.com/pic5/latex/14.png)
x
![](http://thumb.1010pic.com/pic5/latex/184616.png)
=21
![](http://thumb.1010pic.com/pic5/latex/184616.png)
,
x=35;
(2)24-120%x=18,
24-120%x+120%x=18+120%x,
18+120%x=24,
18+120%x-18=24-18,
120%x÷120%=6÷120%,
x=5;
(3)x-4×
![](http://thumb.1010pic.com/pic5/latex/168.png)
=
![](http://thumb.1010pic.com/pic5/latex/36.png)
,
x-
![](http://thumb.1010pic.com/pic5/latex/137.png)
+
![](http://thumb.1010pic.com/pic5/latex/137.png)
=
![](http://thumb.1010pic.com/pic5/latex/36.png)
+
![](http://thumb.1010pic.com/pic5/latex/137.png)
,
x=
![](http://thumb.1010pic.com/pic5/latex/312754.png)
.
分析:(1)先计算x-
![](http://thumb.1010pic.com/pic5/latex/335.png)
x=
![](http://thumb.1010pic.com/pic5/latex/14.png)
x,再在方程的两边同时除以
![](http://thumb.1010pic.com/pic5/latex/14.png)
即可得解;
(2)根据等式的性质,在方程两边同时加上120%x,然后在方程的两边同时减去18,再同时除以120%得解;
(3)先计算4×
![](http://thumb.1010pic.com/pic5/latex/168.png)
=
![](http://thumb.1010pic.com/pic5/latex/137.png)
,再在方程的两边同时加上
![](http://thumb.1010pic.com/pic5/latex/137.png)
得解.
点评:此题考查了根据等式的性质解方程,即等式两边同加、同减、同乘或同除以一个数(0除外),等式的左右两边仍相等;注意等号上下要对齐.