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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?

User Savitri
by
3.5k points

2 Answers

0 votes

Answer:

Unsure, sorry

Explanation:

User Minras
by
3.4k points
3 votes

Answer:

t=6

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

User Tashuhka
by
3.4k points