A ball is thrown straight up from the top of a building that is 400 ft high with an initial velocity of 64 ft/s. The height of t
he object can be modeled by the equation s(t) = -16t^2 + 64t + 400. In two or more complete sentences explain how to determine the time(s) the ball is higher than the building in interval notation.
You play out the equation and say what each part of the equation means. The vertex in this case, because it's a downward facing parabola, is the highest point on the graph. Now since they're kicking a ball, the vertex will be the highest point that the ball will go up to.
Hopefully this helps some. For full points you'll probably have to add a bit of padding and further explanation.
