4x-3y-6z=0,x+2y-7z=o,且xyz不等于0求3x+2y+z\x+2y+3z的值.
问题描述:
4x-3y-6z=0,x+2y-7z=o,且xyz不等于0求3x+2y+z\x+2y+3z的值.
注意!不要抄袭别人的回答,有的不太一样.
答
4x-3y-6z=0,4x-3y=6z (1)
x+2y-7z=o,x+2y=7z (2)
(2)*4-(1)得11y=22z y=2z
∴ x=3z
3x+2y+z\x+2y+3z=14z/10z=7/5