Question

The equation y = -0.0088x² + 0.79x + 15 models the speed x (in miles per hour) and average gas mileage y (in miles per gallon) for a vehicle. What is the best approximation for the average gas mileage at a speed of 60 miles per hour?

1) 15.7 miles per gallon
2) 30.7 miles per gallon
3) 61.9 miles per gallon
4) 62.9 miles per gallon

Answer 1

The best approximation for the average gas mileage at a speed of 60 miles per hour is 30.7 miles per gallon.

Step-by-step explanation:

To find the best approximation for the average gas mileage at a speed of 60 miles per hour, we need to substitute x with 60 in the given equation.

y = -0.0088(60)² + 0.79(60) + 15

Simplifying, we get:

y ≈ 30.68

Therefore, the best approximation for the average gas mileage at a speed of 60 miles per hour is 30.7 miles per gallon.