Ball Dropped from a height

Question

A ball is dropped from a height of 144 ft. It's height h in feet, t is seconds.

h(t)+-16t² + 144

How long after it is dropped will it hit the ground? Show work

Answer 1

First, we need to fix the equation for h(t).

h(t) = -16t² + 144

It hits the ground when h=0, so set h(t)=0 and solve for t.

0 = -16t² + 144

t = √(144 / 16) sec = ? sec