Question 1 of 5
A bike rental company charges a one-time delivery fee and a fixed cost per hour. The graph of the total cost versus the number of hours rented is a line that crosses the cost axis at and passes through the point . Which equation represents the total cost in dollars after renting a bike for hours?
Explanation
The line crosses the cost axis at , so the -intercept is . That means the equation has the form . Since the line passes through , substitute and :
So the equation is
Concept summary
For a linear model in context, use the intercept as the starting value and compute the slope from the change in output over the change in input.