Question

解方程组 2x十y=2 2y十Z=7 x十2z=3

Answer 1

三式相加得：

x+y+z=4

2x+y=2

x+(x+y)=2

x+(4-z)=2

x-z=-2

因为

x+2z=3

3z=5

z =5/3

x= - 1/3

y=2 - 2x=2+2/3=8/3

{x= -1/3

{y=8/3

{z =5/3