4x + 9 = 7x

and

2r - 6 = 7r +24

I am very confused. I don't want simply the answer... a formal to solve these problems will do me a lot of good.. I don't want to fail this assignment (I have 33 questions) so I would like a formula to solve these type of questions rather than just the answer. I already know I asked for help on a question, but I really don't understand the formulas for these type of problems.