我先占个位
1:(2/3+x)*3=8*4/9
2/3+x=32/3
x=30/3=10
2:x-(1/8+16)=82
x=82-(1/8+16)=66-1/8=65又7/8=527/8
3:2/5X+2.8-4.4=0
0.4x-1.6=0
x=4
4:即3x-3-1.6=7.4
3x=2.8
x=14/15
5:即5/6x=15,x=18
列方程解文字题:1:8x-3x=31.5
,5x=31.5
x=6.3
2:2x-23/2=8
x=39/4
3:1/4x=25*1/5-0.8
x=16.8