Please help, Algebra word problem!

Question

Luis wanted to throw an apple to Kim, who was on a balcony 40 feet above him, so he

tossed it upward with an initial speed of 56 ft/sec. Kim missed it on the way up, but then caught

it on the way down. Use the equation h = vt − 16t , where is the initial speed, h is the height 2 v

of the apple measured in feet, and t is time since the apple was thrown measured in seconds.

What was the maximum height of the apple? When did the apple reach its maximum height?

Answer 1

The correct equation for h in feet is

h(t) = -16t² + vt (note the equation given in the question is not correct)

v = 56 ft/s

h(t) = -16t² + 56t

Maximum height occurs at the vertex of the height-vs.-time parabola, which is at

t = -56 / [2(-16)] sec = ? sec

Evaluate h(t) at this value of t to get the maximum height.