3x - y + 2z = 3
2x + y - 4z = 11
7x + y - 5z = 1
首先将 y 消元,
第一式与后两式相加,得
5x - 2z = 14
10x - 3z = 4
还有
-10x + 4z = -28
两式相加,再将 x 消元得
z = -24
那么
10x + 72 = 4
10x = -68
x = -6.8
再看
2x + y - 4z = 11
y - 13.6 + 96 = 11
y - 13.6 = - 85
y = - 71.4

方程组就是
x = -6.8
y = -71.4
z = -24 3x - y + 2z = 3
2x + y - 4z = 11
7x + y - 5z = 1
首先将 y 消元,
第一式与后两式相加,得
5x - 2z = 14
10x - 3z = 4
还有
-10x + 4z = -28
两式相加,再将 x 消元得
z = -24
那么
10x + 72 = 4
10x = -68
x = -6.8
再看
2x + y - 4z = 11
y - 13.6 + 96 = 11
y - 13.6 = - 85
y = - 71.4

方程组就是
x = -6.8
y = -71.4
z = -24