The distance that a car travels between the time the driver makes the decision to hit the brakes and the time the car actually stops is called the braking distance. For a certain car traveling v mi/hr, the braking distance d (in feet) is given by
d = v + (v2/20).
(a) Find the braking distance when v is 65 mi/hr.?d = ? ft??
(b) If a driver decides to brake 120 feet from a stop sign, how fast can the car be going and still stop by the time it reaches the sign??v = ?