a model airplane is shot up from a platform 1 foot above the ground with an initial upward velocity of 56 feet per sec. the height of the airplane above ground after t secs is given by the equation h = -16t^2+56t+1, where h is the height of the airplane in feet and t is the time in secs after it is launched. approximately how long does it take the airplane to reach its max height?

Question

a model airplane is shot up from a platform 1 foot above the ground with an initial upward velocity of 56 feet per sec. the height of the airplane above ground after t secs is given by the equation h = -16t^2+56t+1, where h is the height of the airplane in feet and t is the time in secs after it  is launched. approximately how long does it take the airplane to reach its max height?