解方程 7x+2x=0.81 4(x-6)=36 2x+0.2X2=36

问题描述:

解方程 7x+2x=0.81 4(x-6)=36 2x+0.2X2=36

7x+2x=0.8
9x=0.8
x=4/45
1 4(x-6)=36
14x-84=36
14x=120
x=60/7
2x+0.2X2=36
2.4x=36
x=15