Why Variable is always taken as positive?

I think all of you have question why we use x as variable not "-x"?
So after researching all night I found the answer, so here it is.

If we take +ve sign with variable we find real sign of the answer l.
For e.g.
 +(+ve)=+ve
+(-ve)=-ve
Here if sign of x is negative -ve then answers sign or operation us changed.
If we use - sign then we gave to reverse the sign of answer also.
For e.g.
2+__ =3
1. If value be x then
  2+x=3,
  x=1
2. If value is -x
 2-x=3
 x=-1.
HOPE ALL OF YOU HAVE UNDERSTOOD IF HAVE ANY DOUBT TELL IN COMMENT SECTION.