For an inequality type of question your goal is to isolate the variable, in this case r. It doesn't necessarily which side you leave r on, however it seems easier to isolate it on the right side in this problem.
1. add 9 r to both sides. -7<=4r-3
2. add 3 to both sides to get r by itself, -4<=4r
3. now divide both sides by 4 to isolate r. -1<=r
Hope this helps