2x+y=7,x-3y=3,x=?,y=?
来源:百度知道 编辑:UC知道 时间:2024/05/14 17:53:30
2x+y=7,x-3y=3,x=?,y=?
3(2x+y)=21 6x+3y=21① x-3y=3②
①+②得7x=24
x=7/24
把x=24/7带入②得 y=1/7
晚了一步
x=24/7,y=1/7
解:
2x+y=7(1)
x-3y=3(2)
(1)-(2)*2得
7y=1
y=1/7
将y值代入(1)得
x=24/7
2x+y=7--(1)
x-3y=3--(2)
(1)-(2)×2得
7y=1
y=1/7
将y=1/7带入(1)
2x+1/7=7
x=24/7
x=24/7,y=1/7
解:
2x+y=7(1)
x-3y=3(2)
(1)-(2)*2得
7y=1
y=1/7
将y值代入(1)得
x=24/7
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