From g(x)=x we see a slope of 1, meaning the movies cost $1 per movie. There's no y intercept so this is a proportional relationship.
From the graph f has y intercept $2 and slope (1/2), f(x) = (1/2) x + 2 is the function for the cost of downloading music.
Once we get to 3 downloads, f(3)=g(3) and beyond that music downloads will be cheaper because they only cost 1/2 dollar for each additional one compared to $1 for each movie. But for 2 we have f(2)=3, g(2)=2 so two movies will be cheaper. One of each costs $1 + $2.50, more than either of the other choices.
Answer: B downloading two movies is cheapest
