The answer is "1 second" but how do I set up and solve the problem?

Question

"If an object is thrown upward from the ground with an initial velocity of 16 ft/sec, its height after t seconds is given by h=16t-16t². Find the number of seconds before the object hits the ground."

Answer 1

h(t) = 16t - 16t² = 16t(1 - t)

 

Set h(t) = 0 (i.e. on the ground) and solve for t.

 

t = 0 or 1, but t = 0 is the moment of launch, so the solution is t = 1 second