Question

Joy kicks the ball off the ground . After t seconds , it's height , h (in feet) is given by the formula h(t)= -16t^2 + 64t . What is the maximum height reached by the ball?

Answer 1

64 ft

Explanation:

The given equation can be factored as ...

h(t) = -16t(t -4)

This is the equation of a parabola that opens downward and has zeros at t=0 and t=4. The vertex (maximum) occurs at the value of t halfway between these, at t=2. Filling in t=2, we can find the maximum height to be ...

h(2) = -16(2)(2-4) = 64 . . . . feet