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A bungee jumper falls from a bridge 400 feet above ground. Her height above ground after t seconds is given by the equation h=-16t^2+400 where h is the height of the jumper in feet and t is the time in seconds since her jump. Approximately how long will it take for the bungee jumper to reach 100 feet above the ground on her initial jump?

A.
14 seconds
B.
4.3 seconds
C.
4.4 seconds
D.
4.5 seconds

User Kadidja
by
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2 Answers

1 vote

Answer:

B. 4.3 seconds

Explanation:

Given: The height above ground after t seconds is given by the equation h=-16t^2+400 where h is the height of the jumper in feet and t is the time in seconds since her jump.

To find time to reach the height (h) = 100 ft above the ground, we need to plug h = 100 in the given equation and solve for t.

100 = -16t^2 + 400

Subtract 400 from both sides, we get

100 - 400 = -16t^2 + 400 - 400

-300 = -16t^2

Now divide both sides by -16, we get

-300/-16 = -16t^2/-16

t^2 = 18.75

Now take square root on both sides.

√t^2 = √18.75

t = 4.3 seconds.

User VKen
by
8.0k points
3 votes
The question is asking to choose among the following choices that states the duration that the bungee jumper to reach 100 feet above the ground on her initial jump, base on that, the possible answer would be letter B. 4.3 seconds. I hope you are satisfied with my answer and feel free to ask for more 
User Deepak S
by
7.5k points