已知x+2y-z=8,2x-y+z=18,则8x+y+z= _ .

问题描述:

已知x+2y-z=8,2x-y+z=18,则8x+y+z= ___ .

x+2y-z=8,①
2x-y+z=18,②
由①×2+②×3,得
8x+y+z=70,
故答案为:70.