Let m be the cost of renting a movie and v be the cost of renting a video.
One month Omar rented 3 movies and 5 video games for a total of $41.
3m + 5v = 41
The next month he rented 12 movies and 2 video games for a total of $65.
12m + 2v = 65
So your two equations are:
3m + 5v = 41
12m + 2v = 65
Can you solve it now? Use either substitution or elimination.