Answer:
It does not matter, since, from your second case, [tex]5\sqrt5 +11 = 11+5\sqrt5[/tex].
In general is a matter of personal preference but in general I like to start with a positive number (I like [tex]\sqrt2 -1[/tex] more than [tex]-1+\sqrt2[/tex] since if there's an equal sign before I'm guaranteed to have the two signs mesh together in a few steps).
If everything you are adding together is positive, I just go first come first served and pick a new term in order it appears in the previous passage.
