You can put this solution on YOUR website! I imagine you wish to solve this...to do so, we try to isolate the variable by undoing what is currently being done to it...
Notice that in
2 = 5 + r
the five is being added to r...to undo that, we subtract five from both sides...we get
2 - 5 = 5 + r - 5
and
r = -3
