Answer
The height of the object at $t=0$ seconds is $960$ ft.
The height of the object at $t=3$ seconds is $1008$ ft.
The height of the object at $t=6$ seconds is $768$ ft.
The height of the object at $t=9$ seconds is $240$ ft.
Work Step by Step
The given equation is $h(t)=-16t^{2}+64t+960$.
To find the height of the object when $t=0$, substitute $0$ in for t.
$h(0)=-16(0)^{2}+64(0)+960$
Evaluate: $h(0)=-16(0)^{2}+64(0)+960=960$.
Therefore, the height of the object when $t=0$ is $960$ ft.
To find the height of the object when $t=3$, substitute $3$ in for t.
$h(3)=-16(3)^{2}+64(3)+960$
Evaluate: $h(3)=-16(3)^{2}+64(3)+960=1008$.
Therefore, the height of the object when $t=3$ is $1008$ ft.
To find the height of the object when $t=6$, substitute $6$ in for t.
$h(6)=-16(6)^{2}+64(6)+960$
Evaluate: $h(6)=-16(6)^{2}+64(6)+960=768$.
Therefore, the height of the object when $t=6$ is $768$ ft.
To find the height of the object when $t=9$, substitute $9$ in for t.
$h(9)=-16(9)^{2}+64(9)+960$
Evaluate: $h(9)=-16(9)^{2}+64(9)+960=240$.
Therefore, the height of the object when $t=9$ is $240$ ft.
