｛6x+5y=25 (1)
3x+4y=20 (2)
(2)x2-(1)得：3y=15
y=5
把y=5代入（1）得：6x=0
x=0
原方程组得解是：x=0
y=5
｛6x+5y=25 3x+4y=20
2个回答
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