SOLUTION: The Skywalk is a glass-bottomed platform that hangs over the edge of the Grand Canyon and is suspended 4000 feet above the floor of the canyon. If a tourist shot an arrow straight

Question 1025197: The Skywalk is a glass-bottomed platform that hangs over the edge of the Grand Canyon and is suspended 4000 feet above the floor of the canyon. If a tourist shot an arrow straight up in the air from the observation platform, the arrow's height could be modeled by
H(t) = −16t2 + 240t + 4000
where H(t) is the height of the arrow above the canyon floor in feet t seconds after being shot.
(a) Find H(3) and explain its meaning. (Include units with your numerical answers.)
After, the arrow was at a height of_____.
(b) Use factoring to determine how many seconds before the arrow was at a height of 1536 feet. (Include units with your numerical answer.)
It took about______for the arrow to get to 1536 feet.
(c) Use factoring to determine after how many seconds the arrow would hit the canyon floor. (Include units with your numerical answer.)
After, _____ the arrow hits the canyon floor.
Answer by KMST(5328) (Show Source): You can put this solution on YOUR website!
defined for the time that the arrow is in flight,
and such that ,
is the height of the arrow above the canyon floor in feet seconds after being shot.

(a)
After seconds, the arrow was at a height of feet.

(b)

.
Dividing both sides of the equal sign by we get the equivalent equation
, which we can solve by factoring:
-->-->--> .
does not make sense; it is not in the domain of the function, where it must be ,
so the answer is .
It took about seconds))) for the arrow to get to 1536 feet.

c) When the arrow hits the canyon floor, it is feet above the canyon floor, so
, which means
Dividing both sides of the equal sign by we get the equivalent equation
, which we can solve by factoring:
-->-->--> .
does not make sense; it is not in the domain of the function, where it must be ,
so the answer is .
After seconds, the arrow hits the canyon floor.
RELATED QUESTIONS
The Skywalk is a glass-bottomed platform that hangs over the edge of the Grand Canyon and (answered by KMST)

Have no idea where to even begin to solve this problem. Any help is appreciated. The... (answered by CPhill)

A rocket is fired from the floor of the grand canyon. The height of the rocket, h(t) in (answered by ikleyn)

A mass is suspended by a spring such that it hangs at rest 0.5 m above the ground. The... (answered by ikleyn)

The height, in feet, of a rock,above the Colorado River that is thrown from the north rim (answered by Earlsdon)

You visit the Grand Canyon and drop a penny off the edge of a cliff. The distance the... (answered by Alan3354)

A mass is suspended by a spring such that it hangs at rest 0.5 m above the ground. The... (answered by ikleyn)

a family drove out to the Grand canyon averaging 35 mph they returned using the same... (answered by josgarithmetic,greenestamps)

A family drove to the Grand Canyon, averaging 45 mph. They returned using the same route, (answered by mananth)