Answer:
B, D, E
Step-by-step explanation:
As we know that a pair of quantities that are proportional when they can be expressed in the general form y = kx, where k is the constant of proportionality.
A. A small pizza costs $9.00 and each additional topping costs $0.75
=> the cost to buy the number of pizzas is: y = 0.75x + 9
It is not proportional
B. A health club charges $45 per month
=> The cost for health club y = 45x
It is not proportional
C. A bike rental store charges $20 as a flat fee, plus $5 per hour
=> the cost to rent the bike: y = 5x + 20
It is not proportional
D. A car travels 60 miles in 1 hour, 120 miles in 2 hours, and 180 miles in 3 hours
=> The distance the car travel is: y = 60x
It is proportional
E A student earns $12 for each hour she tutors.
=> The income the student get: y = 12x
It is proportional
Hence, answer B, D, E are correct