4(x+2)=1-5x 3(y+2)=3-2 y/2+x/3=13 y/3-x/4=3 x+y=420 30%x+40%

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/11/09 03:36:38

4(x+2)=1-5x 3(y+2)=3-2 y/2+x/3=13 y/3-x/4=3 x+y=420 30%x+40%y=160*180% 2x-1/5+3y-2/4=2 3x+1/3-3y+2/
4(x+2)=1-5x
3(y+2)=3-2
y/2+x/3=13
y/3-x/4=3
x+y=420
30%x+40%y=160*180%
2x-1/5+3y-2/4=2
3x+1/3-3y+2/4=4/3
x/2+y/3=2
2x+3y=28

4x+8=1-5x
(4+5)x=1-8
x=-7/9
3y=1-6
y=-5/3;
y/2=13-x/3
y=26-2x/3
(26-2x/3)/3-x/4=3
-(2/9+1/4)x=3-26/3
x=12
y=26-24/3=18;
y=420-x
0.3x+0.4(420-x)=160*1.8
-0.1x=120
x=-1200
y=1620;
化简可得2x+3y=2.7 x-y=1/6
x=y+1/6 2(y+1/6)+3y=2.7
y=71/150
x=16/25;
化简3x+2y=12 2x+3y=28
两式相减.y-x=16,y=16+x
3x+32+2x=12
x=-4
y=12

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