Answer:
A. The total cost of the small popcorns
Step-by-step explanation:
Let us suppose Trinity is going to the movies with [tex]x[/tex] number of friends, we know she will pay for only her own movie ticket hence cost of movie ticket will be a constant (say [tex]a[/tex]) for her expense and cost of popcorn will be price of one popcorn (say [tex]b[/tex]) multiplied by number of friends.
considering the situation, her expense will be given by the function-
[tex]f(x) = a + bx[/tex]
comparing this with the given function [tex]8.5 + 6x[/tex], [tex]6x[/tex] will be the total cost of small popcorns.