Question

The fuel economy of a car, measured in miles per gallon, is modeled by the function ƒ(s) = –0.009s2 + 0.699s + 12 where s represents the speed of the car, measured in miles per hour. The point (8,17) lies on the graph of the function. What does the point (8,17) mean in terms of the problem situation? A. When the car is driven at an average of 17 miles per hour, the fuel economy is 8 miles per gallon. B. When the car is driven 8 miles, the fuel economy is 17 miles per gallon. C. When the car is driven at an average of 8 miles per hour, the fuel economy is 17 miles per gallon. D. When the car is driven 17 miles, the fuel economy is 8 miles per gallon.

Answer 1

Answer: The correct option is C.

Explanation:

It is given that the fuel economy of a car, measured in miles per gallon, is modeled by the function $f(s) = -0.009s^2 + 0.699s + 12$ where s represents the speed of the car, measured in miles per hour.

It means the input values are s and output values are f(s).

So the coordinate pair are in the form of (s,f(s)) and it represents that if the car is driven at the average speed of s miles per hour, then the fuel economy is f(s) miles per gallon.

The given point is (8,17) and it is lies on the graph of the function. It means if the car is driven at an average of 8 miles per hour, the fuel economy is 17 miles per gallon.

Therefore, the correct option is C.