解:(1)4x=32.8,
4x÷4=32.8÷4,
x=8.2;
(2)
![](http://thumb.1010pic.com/pic5/latex/4458.png)
:x=
![](http://thumb.1010pic.com/pic5/latex/5882.png)
:
![](http://thumb.1010pic.com/pic5/latex/7.png)
,
![](http://thumb.1010pic.com/pic5/latex/5882.png)
x=
![](http://thumb.1010pic.com/pic5/latex/4458.png)
×
![](http://thumb.1010pic.com/pic5/latex/7.png)
,
![](http://thumb.1010pic.com/pic5/latex/5882.png)
x×
![](http://thumb.1010pic.com/pic5/latex/35289.png)
=
![](http://thumb.1010pic.com/pic5/latex/4458.png)
×
![](http://thumb.1010pic.com/pic5/latex/7.png)
×
![](http://thumb.1010pic.com/pic5/latex/35289.png)
,
x=
![](http://thumb.1010pic.com/pic5/latex/330942.png)
;
(3)
![](http://thumb.1010pic.com/pic5/latex/13.png)
x-
![](http://thumb.1010pic.com/pic5/latex/8.png)
x=4,
![](http://thumb.1010pic.com/pic5/latex/7.png)
x=4,
![](http://thumb.1010pic.com/pic5/latex/7.png)
x×6=4×6,
x=24;
(4)
![](http://thumb.1010pic.com/pic5/latex/14.png)
:2.5=z:6,
2.5z=6×
![](http://thumb.1010pic.com/pic5/latex/14.png)
,
2.5z÷2.5=6×0.6÷2.5,
z=1.44.
分析:(1)根据等式的性质,两边同除以4即可;
(2)先根据比例的性质改写成
![](http://thumb.1010pic.com/pic5/latex/5882.png)
x=
![](http://thumb.1010pic.com/pic5/latex/4458.png)
×
![](http://thumb.1010pic.com/pic5/latex/7.png)
,再根据等式的性质,两边同乘
![](http://thumb.1010pic.com/pic5/latex/35289.png)
即可;
(3)原式变为
![](http://thumb.1010pic.com/pic5/latex/7.png)
x=4,根据等式的性质,两边同乘6即可;
(4)先根据比例的性质改写成2.5z=6×
![](http://thumb.1010pic.com/pic5/latex/14.png)
,再根据等式的性质,两边同除以2.5即可.
点评:在解方程时应根据等式的性质,即等式两边同加上、同减去、同乘上或同除以某一个数(0除外),等式的两边仍相等,同时注意“=”上下要对齐.