若lxl=3,lyl=5,lzl=7,且x>y>z,求x+y-z得值

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/19 09:43:18
若lxl=3,lyl=5,lzl=7,且x>y>z,求x+y-z得值
xQJ0ޛP^$=!Eу+B=.Em৬i i׭C=fޛy0)0 Oc(j>.I6Rx xqCc3*Ke9jR@a`ѭ|v Zp`SXA;B~Am;w6X\]iqLbzN wƋ*W׹, 3/H۴L"+mgFW7[PNY$(i /d1

若lxl=3,lyl=5,lzl=7,且x>y>z,求x+y-z得值
若lxl=3,lyl=5,lzl=7,且x>y>z,求x+y-z得值

若lxl=3,lyl=5,lzl=7,且x>y>z,求x+y-z得值
lxl=3,lyl=5,lzl=7,且x>y>z
所以x=-3时,y= -5,z=-7
那么x+y-z
= -3+(-5)-(-7)
= -1
或x= 3时,y= -5,z=-7
那么x+y-z
= 3+(-5)-(-7)
=5

答案是:5或者-1

当x=3,y=-5,z=-7时满足条件x>y>z。x+y-z等于5
当x=-3,y=-5,z=-7时满足条件x>y>z。x+y-z等于-1

∵lxl=3,lyl=5,lzl=7
又∵x>y>z
∴y=-5,z=-7,x=±3
当x=3时
x+y-z
=3-5+7
=5
当x=-3时
x+y-z
=-3-5+7
=-1
∴x+y-z=5或-1