The table shows the outputs y for different inputs x:
input
(x) 5 6 7 8
output
(y) 2 5 8 11
part a: do the data in this table represent a function? justify your answer. (3 points)
part b: compare the data in the table with the relation f(x) = 2x + 13. which relation has a greater value when x = 7? (2 points)
part c: using the relation in part b, what is the value of x if f(x) = 75? (5 points)

the revenue of the fitness center, y, is the product of two factors: the number of members and the fee paid by each member. there are 320 members now, but number of members goes down by 10 for each $5 increase in fees, so if x is the number of $5 price increases then members is equal to (320 - 10x). since the fee is currently $45, and the fee increases by $5 for every price bump x, the fee is given by (45 + 5x). so, revenue y is given by y = (320 - 10x)(45 + 5x).