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题目:解方程组:x-y/2-x+y/5=1,3(x-y)+2(x+y)=6

问题描述:

x-y/2-x+y/5=13(x-y)+2(x+y)=6



最佳答案:

解:

(x-y)/2-(x+y)/5=1

5(x-y)-2(x+y)=10

5x-5y-2x-2y=10

3x-7y=10 ①

3(x-y)+2(x+y)=6

3x-3y+2x+3y=6

5x-y=6 ②

②×7-①可得,35x-3x=42-10,即x=1,

将x=1代入②中可得,5-y=6,即y=-1

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