Question

A model rocket is launched from the roof of a building. It’s height can be found by using h(t)= -5t^2 + 30t + 9 where h is its height in meters and t is the time after the launch in seconds, as shown in the graph. Find the maximum height of the rocket. Show work

Answer 1

The vertex of the parabola is found by setting the derivative of the function equal to zero and solving for t. The derivative of h(t) is h'(t) = -10t + 30. Setting this equal to zero and solving for t, we get t = 3.

Substituting t = 3 into h(t), we get h(3) = -5(3)^2 + 30(3) + 9 = 55 meters.