①.4(x-y-1)=3(1-y)-2(1/2)x+(1/3)y=2 ②.x+2y=(y-3x)/4=(2x-1)/3

①.4(x-y-1)=3(1-y)-2(1/2)x+(1/3)y=2 ②.x+2y=(y-3x)/4=(2x-1)/3
①.4(x-y-1)=3(1-y)-2
(1/2)x+(1/3)y=2
②.x+2y=(y-3x)/4=(2x-1)/3

①.4(x-y-1)=3(1-y)-2(1/2)x+(1/3)y=2 ②.x+2y=(y-3x)/4=(2x-1)/3
1.4x-4y-4=3-3y-2 ①
(1/2)x+(1/3)y=2 ②
由1.2 得 x=2 y=3
2.x+2y=(y-3x)/4①
x+2y=(2x-1)/3②
①两边同乘4
②两边同乘3
4x+8y=y-3x①
3x+6y=2x-1②
由1.2得x=1/5 y= -1/5

①4x-4y-4=3-3y-2
y=4x-5
y=(2-0.5x)*3
即有4x-5=(2-0.5x)*3
解得：x=2,y=3
②x+2y-(y-3x)/4=0
X=-Y
x+2y-(2x-1)/3=0
X=-6Y-1
即有：Y=1+6Y
解得，Y=-0.2
X=0.2

①.4(x-y-1)=3(1-y)-2
两边去括号得4x－y－5=0
y=4x－5
(1/2)x+(1/3)y=2
两边×6得3x＋2y=12
把y=4x－5带入得x=2,y=3
②由x+2y=(y-3x)/4
两边×4简化得x＋y=0即x=-y
由x+2y=...

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①.4(x-y-1)=3(1-y)-2
两边去括号得4x－y－5=0
y=4x－5
(1/2)x+(1/3)y=2
两边×6得3x＋2y=12
把y=4x－5带入得x=2,y=3
②由x+2y=(y-3x)/4
两边×4简化得x＋y=0即x=-y
由x+2y=(2x-1)/3
两边×3简化得x＋6y＋1=0
所以x=1/5,y=-1/5
x+2y=(2x-1)/3

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①。4(x-y-1)=3(1-y)-2 ②。x+2y=(y-3x)/4=(2x-1)/3
(1/2)x+(1/3)y=2 依题意得
整理得 ...

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①。4(x-y-1)=3(1-y)-2 ②。x+2y=(y-3x)/4=(2x-1)/3
(1/2)x+(1/3)y=2 依题意得
整理得 x+2y=(y-3x)/4
4x-y=5 ① (y-3x)/4=(2x-1)/3
3x+2y=12 ② 整理得
①*2+②得 x+y=0 ①
11x=22 -17x+3y=-4 ②
x=2 ①*3-②得
将x=2带入①得 20x=4
8-y=5 x=1/5
y=3 将x=1/5带入①得
1/5+y=0
x=2 y=-(1/5)
y=3
x=1/5
y=-(1/5)

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