Slope-Intercept Equations in Real-Life Cost Problems

A car rental company charges a flat fee of $20 plus $0.15 per mile driven. Write the slope-intercept equation that represents the total cost (C) in terms of miles driven (m).

• C = 0.15m - 20

• C = 20 + 0.15m^2

• C = 20m + 0.15

• C = 0.15m + 20

If a bike rental shop charges $10 for the first hour and $5 for each additional hour, write the slope-intercept equation for the total cost (C) after h hours.

• C = 5h + 10

• C = 10h

• C = 5h + 5

• C = 10 + 5h

Graph the equation from question 1. What is the total cost if 100 miles are driven?

• $25.00

• $75.00

• $50.00

• $100.00

A gardener charges $50 for a service plus $25 for each additional hour worked. Write the slope-intercept equation for the total cost (C) in terms of hours worked (h).

• C = 50h + 25

• C = 50 + 25h

• C = 25h + 50

• C = 25h - 50

Using the equation from question 4, graph the total cost for 3, 5, and 7 hours of work. What do you notice about the slope?

• The slope varies, indicating a non-linear relationship.

• The slope is negative, suggesting a decrease in total cost with more hours.

• The slope is zero, meaning total cost does not change with hours worked.

• The slope is constant, indicating a linear relationship between hours worked and total cost.

A phone plan costs $30 per month plus $0.10 per text message. Write the slope-intercept equation for the total monthly cost (C) in terms of the number of text messages (t).

• C = 30 + 0.10t

• C = 30 + 0.05t

• C = 0.10 + 30t

• C = 30t + 0.10

Graph the equation from question 6. How much would the total cost be if 200 text messages are sent?

• $20.00

• $5.00

• $15.00

• $50.00

A delivery service charges a base fee of $15 plus $2 per mile. Write the slope-intercept equation for the total cost (C) in terms of miles (m).

• C = 15 + 2m

• C = 2m + 15

• C = 2m - 15

• C = 15m + 2

Using the equation from question 8, graph the total cost for 5, 10, and 15 miles. What does the slope represent in this context?

• The slope indicates the fixed cost of the trip.

• The slope shows the total distance traveled.

• The slope represents the variable cost per mile.

• The slope represents the average speed of the vehicle.

A subscription service charges $12 per month plus $1 for each additional movie rented. Write the slope-intercept equation for the total cost (C) in terms of the number of movies rented (m).

• C = 12m + 1

• C = 12 + 1m

• C = 1m + 12

• C = 1m + 1