（1)x=10y,3x-2y=12 (2)x=7,2x-3y=-4 (3)2x+y=32,2x=y 今天我要用

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/05/26 04:04:19

（1)
x=10y代入3x-2y=12
3*10y-2y=12
28y=12
y=3/7
x=30/7
(2)x=7代入2x-3y=-4
14-3y=-4
3y=14+4
y=8
x=7
(3)2x+y=32,2x=y
y=2x代入
2x+2x=32
4x=32
x=8
y=2x=16

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