The equation y = -4.2t^2 + 42t + 18.9 describes the height (in meters) of a ball tossed up in the air at 42 meters per second from a height of 18.9 meters from the ground, as a function of time in seconds. In how many seconds will the ball reach maximum height?
+36916 THis is a dome shaped parabola....the max will occur at t = - b/2a = - 42 /(2*(-4.2)) = 5 seconds
