The cost of driving a car includes both fixed costs and mileage costs. Assume that it costs $150.90 per month for insurance and car payments and $0.48 per mile for gasoline, oil, and routine maintenance.
(a). Find values for m and b so that y = mx + b models the monthly cost of driving the car x miles.
(b). What does the value of b represent?

Question

The cost of driving a car includes both fixed costs and mileage costs. Assume that it costs $150.90 per month for insurance and car payments and $0.48 per mile for gasoline, oil, and routine maintenance. 
(a). Find values for m and b so that y = mx + b models the monthly cost of driving the car x miles. 
(b). What does the value of b represent?

anonymous · Answer

$.48$ per mile means if you drive say $x$ miles then your cost is $.48x$ dollars
add that to the 150.90 per month and the cost per month is 
$$y=.48x+150.90$$

anonymous · Answer

$b=150.90$ is the cost even if you drive no miles.
on the graph of $y=.48x+150.90$ , $150.90$ would be the $y$ intercept, where the line crosses the $y$ axis