i don't know get this question

1. last saturday emily rented 4 movies from the video store. this saturday she rented 2 movies. let x represent the cost of renting each movie. write and simplify an expression for how much more emily spent last week renting movies?

2. if it costs $4 to rent each movie, how much more money did emily spend last week renting movies?

1.

4x - 2x =
2x =

2.
4(4) - 2(4) = $8