For a certain driver the stopping distance in feet is given

For a certain driver, the stopping distance in feet is given by   0.04v²+ 0.9v where v is the velocity of the car. Find the stopping distance when a car is traveling 60 mph.

Solution

distance d = 0.04v^2 +0.9v

v = 60mph

Plug v=60 in equation for d:

d = 0.04*60^2 + 0.9*60 = 198 miles