x + 2y = 1 1/3
+x - y =+1/3
3y = ?
not just and answer
No ideas at all? From the problems you have posted, I would think that an algebra I problem like this would be no challenge.
solve for x in the 1st, and substitute it into the 2nd. Then solve for 3y.
Just subtract them as they are to get
3y = ....