Modeling Linear Equations

A driving range charges $4 to rent a golf club plus $2.75 for every bucket of golf balls you hit. Write an equation that shows the total cost c of hitting b buckets of golf balls.

• c = 2.75b + 4
• c = 2.75b
• c =  4b- 2.75
• c = 2.75b - 4

The start up cost to join eTunes music is $7.95 plus $0.95 per song downloaded.  Write a linear equation that could be used to find how many songs he downloaded.

• y = 0.95x + 7.95
• y = 7.95x + 0.95
• y = 0.95x - 7.95
• y = - 0.95x + 7.95

You plan to go snowboarding. The resort charges $15 an hour in addition to $25 to rent a board. Write an equation that represents the cost to go snowboarding for the day.

• y=15x-25
• 15x+25y=100
• 25x+y=15
• y=15x+25

Bob has $150 in his savings account and saves $40 per month.  Which equation represents the amount Bob has in his account after x months?

• y = 150 + 40
• y = 40x + 150
• y = 150x + 40

Which equation shows the number of bottles left after x days?
A family buys a case of water with 48 bottles and drinks 5 bottles per day.

• y = 48x + 5
• y = -5 + 48x
• y = -5x - 48
• y = 48 - 5x

Lee charges $3 for a basket and $2.50 for each pound of fruit picked at the orchard. Write an equation in y = mx + b form for the total cost of x pounds of fruit from the orchard.

• y = 3x + 2.5
• y = 2.50x + 3
• y = 2.50x 
• y = 3x + 2.50

At Joe's Clown Car Rental Agency, renting a car costs $35 plus $0.75 for every mile it is driven. 

• y = x(35 + 0.75)
• y = 35x + 0.75
• y = 0.75x + 35
• y = 0.75(x + 35)

d=125 + 80n models the amount of money (d) in the register after selling n tickets. How much money does she have in the register before selling any tickets? 

• $125
• $80
• $205
• $45

A holiday meal costs $12.50 a person plus a delivery fee of $30.  Which equation represents the amount a holiday meal costs, including delivery, for x people?

• y = 30 + 12.5x 
• y = 12.5 + 30
• y = 12.5 + 30x

A fitness club opens with 80 members. Each month the membership increases by 15 members. Which equation represents the relationship between the number of months the club has been opened, x, and the total fitness club membership, y?

• y=15x
• y=15x+80
• y=x+15
• y=80x+15