解方程组:x-y=3.2y+3(x-y)=11

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解方程组:x-y=3.2y+3(x-y)=11解方程组:x-y=3.2y+3(x-y)=11解方程组:x-y=3.2y+3(x-y)=11x-y=32y+3(x-y)=11=>2y+3=11那么y=4

解方程组:x-y=3.2y+3(x-y)=11
解方程组:x-y=3.2y+3(x-y)=11

解方程组:x-y=3.2y+3(x-y)=11
x-y=3
2y+3(x-y)=11
=>2y+3=11 那么y=4 x=7

x-y=3
y=x-3
代入2y+3(x-y)=11
2y+3x-3y=11
3x-y=11
3x-(x-3)=11
2x=14
x=7
y=x-3=4

该方程组可化简为x-y=3 ①
3x-y=11②
① 式乘3得:3x-3y=9③
用③式减①式得-2y=-2
所以y=1,代入①得x=4