Optional Challenge: Due November 10

Room 1 and Room 2 have 58 students in total. 4 students are transferred from Room 1 to Room 2. Now the two rooms have the same number of students. How many students were there in each room before the transfer?

https://drive.google.com/file/d/0B8-gXqit3js-WndidDY3cE90SWR0dTZCLTJlQ3E2ZE92dHJV/view?usp=sharing