Interpreting Linear Functions Review

Derek works at Subway making $9.25 an hour.  The function d(x)=9.25x tells us how much money Derek makes after x hours of working.  What is the meaning of d(4)=37?

• After 4 hours of work, Derek makes $37.

• Derek needs $4 more to have $37 total.

• After working for 4 days, Derek makes $37 total.

• After 4 hours of work, Derek now makes $37 an hour instead of $9.25.

A company is selling bubble gum.  The function g(x)=3x+4 tells the company how much to charge if someone buys x packages of bubble gum.  Find g(8) and tell what it means within the context of the problem.

• g(8)=8.  This means that after 8 packages of gum, the company makes $8.

• g(8)=42.  This means that 8 packages of gum costs $42.

• g(8)=28.  This means that 8 packages of gum costs $28.

• g(8)=24.  This means that 8 packages of gum costs $24.

According to the graph, at what speed is this car traveling in miles per hour?

• 80 mph

• 20 mph

• 40 mph

• 160 mph

Tim bought a new phone. He paid $125 on the day of purchase, then $50 per month until it was paid off. What linear equation models this situation?

• y = 50x - 135

• y = 50x + 125

• y = 125 + 50

• y = 50x

What is the rate of change demonstrated in this graph?

• 2 cm per hour

• ¹/₄ cm per hour

• ¹/₂ cm per hour

• 4 cm per hour

What does the slope represent in this situation?

• The sloth runs 1 feet in 3 minutes

• The sloth runs 3 feet in 1 minute

• The sloth runs fast

• The sloth runs 6 feet in 1 minute

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

Which of the following points is a y-intercept?
(-2,3) (4, -2) (0, 5) (-9,0)

• (-9,0)

• (-2,3)

• (4,-2)

• (0,5)

Which of the following is another meaning of y-intercept?

• location

• initial value

• total

• constant rate

Dorothy loves to make cakes.  The following table shows how the number of eggs that she has left changes as she makes cakes.
What is the meaning of the y-intercept?

• She uses 5 eggs for every 2 cakes.

• She started with 47 eggs.

• She uses 47 eggs for every 0 cakes.

• She started with 5 eggs.