Question

+y+z=18 8x+6y+6z=112 2y+z=22 这个方程怎么解?

Answer 1

{x+y+z=18 (1)

{8x+6y+6z=112 (2)

{2y+z=22 (3)

(2)-(1)×6得

8x-6x=112-18×6

2x=4

x=2

将x=2代入（2）得

6y+6z=112-2*8

6y+6z=96

y+z=16 (4)

(3)-(4)得

y=6

将y=6代入4得出

z=10

所以解得

{x=2

{y=6

{z=10