题目内容
当x=-2时,的值是8.当x=2时,的值是_____.
(1)当x<5时,的值是 ( )
A.x-5 B.5-x C.5+x D.-5-x
(2)当a>0时,化简等于 ( )
A.0 B.2a C.-2a D.a
(3)若x<-2,化简|x+2|-等于 ( )
A.2x B.2x-4 C.-4 D.4
当x=3时,的值是________,当a=3,b=9时,的值是________.