Final answer:
The slope in the rental company's equation C = 40 + 0.05m is 0.05, representing that the cost increases by $0.05 for each additional mile driven. The y-intercept is 40, indicating the flat fee charged before mileage is considered.
Step-by-step explanation:
When we look at the rental car company's equation, C = 40 + 0.05m, it represents a linear relationship between the total cost C and the mileage m.
Here, the slope of the equation is 0.05. The slope signifies the rate at which the total cost increases for each additional mile driven.
In simpler terms, for every mile you drive, you pay an additional $0.05 on top of the flat fee. The y-intercept of the equation, which is 40, represents the flat fee charged, which is the initial cost before any mileage is added.