解方程组:x+y+z=3(1)x+2y+3z=6 (2)2x+y+z=5 (3)

问题描述:

解方程组:x+y+z=3(1)x+2y+3z=6 (2)2x+y+z=5 (3)
要有过程喔!谢谢

(3)-(1):
x=2
代入(1)(2):
y+z=1 (4)
2y+3z=4 (5)
(5)-(4)*2:
z=2
代入(4):
y=-1