(7.2-x)=(10.8-x)乘1/4

问题描述:

(7.2-x)=(10.8-x)乘1/4

x=6

36/5-x=27/10-1/4x
5/4x=27/10 - 36/5
5/4x=9/2
x=18/5

(7.2-x)=(10.8-x)*1/4
7.2-x =10.8*1/4-1/4x
将含有未知数的项都移到方程的左边,数字移到右边
1/4x-x=10.8*1/4-7.2
-3/4x=2.7-7.2
-3/4x=-4.5
x=6
不明白的话尽管提出来~

两边分别乘以4得
4(7.2-x)=10.8-x
28.8-4x=10.8-x
移项
18=3x
得x=6

(7.2-x)=(10.8-x)×1/4
(7.2-x)÷1/4 =(10.8-x)
28.8-4x=10.8-x
28.8=10.8-x+4x
28.8=10.8+3x
3x=28.8-10.8
x=18÷3
x=6