Model the total stopping distance by the equation y = x2/170 + x/5, where x represents the speed in km/h and y represents the total stopping distance in meters.
a. Graph this equation for the values of x, where x ≤ 100 km/h.
b. Use the graph to approximate the stopping distance for a car traveling at 60km/h.
c. Use the graph to approximate the speed for a car that stops completely after 60 meters.