Question

A book club charges a membership fee of $20 and then $12 for each book purchased. Write a function to represent the change, y, of membership in the club based on the number of books purchased, x.

Answer 1

It is y = 12x + 20.
You start with 20 as the y-intercept because that is the starting amount that you paid. The constant rate of change is 12 dollars per book. So, 12 time however many books written as 12x. Hope that helps! :)