问题
选择题
已知|x|=0.19,|y|=0.99,且x<0,则x-y的值为( )
A.1.18或-1.18
B.0.8或-1.18
C.0.8或-0.8
D.1.18或-0.8
答案
由题意得,x=-0.19,y=±0.99,
①当x=-0.19,y=-0.99时,x-y=-0.19+0.99=0.8;
②当x=-0.19,y=0.99时,x-y=-0.19-0.99=-1.18.
故选:B.
已知|x|=0.19,|y|=0.99,且x<0,则x-y的值为( )
A.1.18或-1.18
B.0.8或-1.18
C.0.8或-0.8
D.1.18或-0.8
由题意得,x=-0.19,y=±0.99,
①当x=-0.19,y=-0.99时,x-y=-0.19+0.99=0.8;
②当x=-0.19,y=0.99时,x-y=-0.19-0.99=-1.18.
故选:B.