题目太多了请分开求助,我好多赚点采纳数哈:) 多谢啦
4×（0.8-x）=1.4
0.8-x = 1.4 ÷4 = 0.35
x = 0.8 -0.35 = 0.45
5+2/3x-1/2x=12
(2/3x-1/2x)=12 -5
(4-3)x /6 = 7
x = 6x7 = 42