Slope Intercept in Context

The cash register deducts $2.50 from a $25 Coffee Cafe gift card for every medium coffee that customer buys. An equation is written to calculate the total amount on the gift card. What is the meaning of the y-intercept in the equation?

• The change in the amount of money spent

• The ending value on the gift card

• The amount of money spent each visit

• The initial value of the gift card

The graph represents the amount John pays for his cell phone service: a monthly fee plus a charge for each minute he uses his phone. What does the y-intercept indicate?

• His monthly fee is $0

• His rate per minute is $0.40

• His monthly fee is $20

• His rate per minute is $0.20

In order to join an online learning community, there is a $20 startup fee and a $5 monthly fee. Write an equation in slope-intercept form that models this situation.

• y = 20x + 5

• y = 5x + 20

• x = 20y + 5

• x = 5y + 20

In order to become a member of the library all-star members club, there is a $40 sign up fee and a $2 monthly fee. Write an equation in slope-intercept form that models this situation.

• 40 = 2x

• 2 = 40x

• y = 2x + 40

• y = 40x + 2

The U.S. Bureau of the Census predicted that the population of Florida would be about 17.4 million in 2010 and then would increase by about 0.22 million per year until 2015. Which of the following linear models predicts the population, y, of Florida (in millions) in terms of x, the number of years since 2010.

• y = 17.4x + 0.22

• y = -0.22x + 17.4

• y = 0.22x + 17.4

• y = -17.4x + 0.22

Suppose that a bike rents for $4 plus $1.50 per hour. Write an equation in slope-intercept form that models this situation.

• 4 = 1.50x

• 1.50 = 4x

• y = 1.50x + 4

• y = 4x + 1.50

Using the equation from Question 6 {y = 1.50x + 4}, how much would it cost someone to rent a bike for 6 hours?

• $6

• $24

• $9

• $13

Cameron is designing a calendar as a find-raising project for math class. The cost of printing is $500, plus $2.50 per calendar. Write an equation in slope-intercept form that models the total cost of printing the calendars.

• y = 2.50x + 500

• y = 500x + 2.50x

• y = 500 - 2.50x

• y = 2.50x - 500

If each calendar from Question 9 sells for $5, how many calendars will Cameron need to sell to break even? (“Break even” means you don’t end up making or losing any money.”) {y = 2.50x + 500}

• 100 calendars

• 200 calendars

• 500 calendars

• 1000 calendars

When visiting Baltimore, Maryland, you need to rent a taxi to get from your hotel to the National Aquarium. The taxi company charges a flat fee of $3.00 for using the taxi and $0.75 per mile. Write an equation in slope-intercept form that models this situation.

• y = 0.75x + 3

• y = 3x + 0.75

• y = 3x - 0.75

• y = 0.75x - 3