solve and multiple solutions



  Hi all. I've a (probably stupid) problem trying to solve an equation
in the form a^2=1. If i try the following:

globalsolve: true$
solve(b^2=1);

I get:
[b=-1,b=1]

which it's obviusly the correct solution, but i'd like to have the
assignment too! (i.e. b:-1)
I know that the question it's "what 'b' to choose for the assignment?",
so i'm wondering how can i solve this kind of equation, having the
assignment done too...
  Any hints?

Thanks,
  Giovanni