Question

3x-y+z=3 2x+y-3z=11 x+y+z=12是连式

Answer 1

3x-y+z=3 (1)

2x+y-3z=11 (2)

x+y+z=12 (3)

(1)+(3)

4x+2z=15 (4)

(2)-(3)

x-4z=-1 (5)

(4)*2+(5)

9x=29

x=29/9

x=29/9代入（5）

29/9-4z=-1

z=19/18

y=139/18

x=29/9,y=139/18,z=19/18