Question

An object is launched from the roof of a building 192
feet above the ground. The object's height (in feet)
after t seconds is given by the function
h(t) = -1672 +64t + 192
B) How many seconds does it take the object to hit the
ground?

Answer 1

Answer:

Unsure, sorry

Step-by-step explanation:

Answer 2

Answer:

t=6

Step-by-step explanation:

h(t) = -16t^2 +64t + 192

We want h(t) =0

0 = -16t^2 +64t + 192

Factor out -16

0 = -16 (t^2 -4t -12)

Factor.  What terms multiply to -12 and add to -4   -6*2 = -12  -6+2 = -4

0 = -16(t-6)(t+2)

Using the zero product property

0=t+2     0=t-6

t = -2   t=6

But t=-2 happens before the event occurs   so the solution is t=6