解方程组2x+3y=7x+3y=9，①﹣②得_刷题宝

题干

解方程组2x+3y=7x+3y=9，①﹣②得（　　）

A：3x=2

B：3x=﹣2

C：x=2

D：x=﹣2

上一题下一题 0.0难度选择题更新时间:2019-07-26 03:37:45

答案(点此获取答案解析）

D

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