一道三元一次方程式.
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/08/18 14:37:32
一道三元一次方程式.
![](http://img.wesiedu.com/upload/b/d4/bd4f2c6c738db616f3e9f41328f26843.jpg)
![](http://img.wesiedu.com/upload/b/d4/bd4f2c6c738db616f3e9f41328f26843.jpg)
![一道三元一次方程式.](/uploads/image/z/20153025-9-5.jpg?t=%E4%B8%80%E9%81%93%E4%B8%89%E5%85%83%E4%B8%80%E6%AC%A1%E6%96%B9%E7%A8%8B%E5%BC%8F.)
3x-y+z=3(1)
2x+y-3z=11(2)
x+y+z=12(3)
(1)+(2)
5x-2z=14(4)
(1)+(3)
4x+2z=15(5)
(4)+(5)
9x=29
x=29/9
(2)-(3)
x-4z=-1
4z=29/9+1
4z=38/9
z=19/18
代入(3)
29/9+y+19/18=12
58/18+y+19/18=12
y=139/18
x=29/9
y=139/18
z=19/18
2x+y-3z=11(2)
x+y+z=12(3)
(1)+(2)
5x-2z=14(4)
(1)+(3)
4x+2z=15(5)
(4)+(5)
9x=29
x=29/9
(2)-(3)
x-4z=-1
4z=29/9+1
4z=38/9
z=19/18
代入(3)
29/9+y+19/18=12
58/18+y+19/18=12
y=139/18
x=29/9
y=139/18
z=19/18