Since R is the midpoint, both sides will be equal so you would set the equations equal to each-other and solve like this
3x+8= 5x-6
+6. +6
3x + 14 =5x
-3x. -3x
14= 2x.
You would then simply x by diving both sides by two to get x=7.
Plugging that into the equation of SR ( that is what we are trying to find) your answer is 29.
( SR= 3(7) +8
SR = 21+8
SR= 29 )
Hope this helps!
