the boxes are equivalent so the one with a single dash is equal to the other with a single dash.
the one with 2 dashes is equal to the other with 2 dashes so on and so forth
SR=LM
LM=9x+27
RS=135
9x+27=135
so I solve it in my own weird way but you can solve it differently. 135-27=108
108/9=12
so your answer is 12
