Respuesta :
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
Answer:
Step-by-step explanation:
Proportionality constant is given by the formula,
y = kx
Where,
y is the dependent factor
x is the independent factor
A. A small pizza costs $9.00 and each additional topping costs $0.75
Let pizza be x, toppings be c and cost = y
y = x + c - linear form
B. A health club charges $45 per month.
Let charges be y, cost be c and months be x
y = c/x - inverse relationship
C. A bike rental store charges $20 as a flat fee, plus $5 per hour.
Let charges be y, flat fee be c, charge rate be t and hour be x
y = c + (t × x) - linear form
D. A car travels 60 miles in 1 hour, 120 miles in 2 hours, and 180 miles in 3 hours.
Let distance be y and hours of travel be x
y = 60 × x
E. A student earns $12 for each hour she tutors.
Let earnings be y and hours be x
y = 12 × x
Note: All proportional functions are linear, but not all linear functions are proportional.
From the above,
A, C, D, E Are all proportional.
