Real World Linear Functions

If chocolate chip cookies cost $3.00 per cookie plus $2 for boxing them up in a decorated box, what would the expression be?

• y = 3 + 2x

• y = 3x + 2

• y = 3x + 2x

• y = 5x

A plumber charges $50 to make a house call plus $40 for each hour worked. Write an equation to represent this situation.

• y = 50x + 40

• y = 50x + 40x

• y = 50 + 40x

• y = 90x

Speedy Boat Rental charges a $15 deposit fee plus $2 for each hour of use to rent a paddle boat.  Write an equation for C, the total cost, to rent the boat for h hours.

• h = 2C + 15
• C = 15h + 2
• h = 15C + 2
• C = 2h + 15

The Roaming Cell Phone Company charges $15.00 per month plus $0.20 per minute of airtime usage.  If Juanita uses x minutes of airtime, what is an equation that can be used to determine her monthly cell phone bill (C)?

• C = 15 + 0.20x
• C =15 (0.20x)
• C = 15 + x + 0.20
• C = 0.20 + 15x

Bob's Plumbing charges $15 per hour plus a service fee of $40 for coming out to your house. Which equation models this situation?

• y = 15x + 40

• y = 40x + 15

• y = 15x

• y = 15x - 40

Dexter's Gym charges a one-time registration fee of $40 and $20 each month. The total fee after x months is $340. Which equation models this situation?

• 40x + 20 = 340

• 20x + 40 = 340

• 20x - 40 = 340

• 20 + 340 = 40x

Scott's Automotive charges $35 for each car plus $7 per hour. Write an equation that represents this scenario if Kylie was charged $63.

• 35x + 7 = 63

• 7x = 63

• 7x - 35 = 63

• 7x + 35 = 63

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

• y = 12.50 + 30x

• y = 30 + 12.50x

• y = 12.50 + 30

• 12.50x = 30

Mrs. Besonen took her kids to see Frozen 2. She bought the big popcorn bucket for $10 and then $1.50 for every refill. Write an equation to represent this situation.

• y = 1.50 + 10x

• y = 1.5x + 10

• y = 1.50 + 10

• 1.50x = 10

Eddie's Electric charges $90 per hour plus a $50 traveling fee. Which equation models this scenario?

• y = -50x + 90

• y = 90x + 50

• y = -90 - 50x

• y = 50 - 90x