解几个方程0.5x-2(0.2x-0.1)=0.8 x-6=3\5x+2 5x-{1-2[x+(x-2)]}x=1-x/3+x/9-x/27 2x+1=2/3x+7/3 69-x=3/4[78-(x+1)]4（x+3)-2(x+7)=6x+105x={1-2[x+(x-2)]}

解几个方程0.5x-2(0.2x-0.1)=0.8 x-6=3\5x+2 5x-{1-2[x+(x-2)]}x=1-x/3+x/9-x/27 2x+1=2/3x+7/3 69-x=3/4[78-(x+1)]4（x+3)-2(x+7)=6x+105x={1-2[x+(x-2)]}
解几个方程
0.5x-2(0.2x-0.1)=0.8 x-6=3\5x+2 5x-{1-2[x+(x-2)]}
x=1-x/3+x/9-x/27 2x+1=2/3x+7/3 69-x=3/4[78-(x+1)]
4（x+3)-2(x+7)=6x+10
5x={1-2[x+(x-2)]}

解几个方程0.5x-2(0.2x-0.1)=0.8 x-6=3\5x+2 5x-{1-2[x+(x-2)]}x=1-x/3+x/9-x/27 2x+1=2/3x+7/3 69-x=3/4[78-(x+1)]4（x+3)-2(x+7)=6x+105x={1-2[x+(x-2)]}
0.5x-2(0.2x-0.1)=0.8 0.5X-0.4X+0.2=0.8 0.1X=0.6 X=6
x-6=3\5x+2 X-3X/5=5 2X/5=8 X=20
5x-{1-2[x+(x-2)]}
x=1-x/3+x/9-x/27 X+X/3-X/9-X/27=1 32X/27=1 X=27/32
2x+1=2/3x+7/3 2X-2X/3=7/3-1 4X/3=4/3 X=1
69-x=3/4[78-(x+1)] 276-4X=234-3X-3 276-234=-3X+4X X=42
4（x+3)-2(x+7)=6x+10 X+3-2X-14=6X+10 6X-X+2X=3-14-10 7X=-21 X=-3

0.5x-0.4x=0.8+0.2 x-3/5x=2+6
0.1x=1 2/5x=8
x=0.1 x=1/20