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An acorn falls from the branch of the tree to the ground 25 feet below. The distance, s, that the acorn is from the ground as it falls is represented by the equation S(t)=16ft+25 where t is the number of seconds. For which interval of time is the acron moving through the air?

User Minutis
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2 Answers

6 votes
The equation can be rewritten as 45t=16+25 (since 45 is the distance the acorn feel from the tree or s). You would then add 16 and 25 ft together to get 41 and change the equation to 45t=41. Divide 45 from both sides to get approximately 0.9 seconds as your answer.
User Najib Fadil
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8.3k points
3 votes

Answer:

1.25 seconds

Explanation:

Given the function: S(t) = –16*t^2 + 25

where S is the distance from the ground in feet and t is time in seconds.

When the acorn hits the ground its distance is zero, replacing into the equation we get:

0 = –16*t^2 + 25

-25/(-16) = t^2

t = √1.5625

t = 1.25 seconds

User Nirav Modh
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6.0k points