SOLUTION: 4. A construction worker drops a tool from the top of a building that is 455 feet tall. The function h = -16t² + 455 gives the height at any time t seconds. How much time does it

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: 4. A construction worker drops a tool from the top of a building that is 455 feet tall. The function h = -16t² + 455 gives the height at any time t seconds. How much time does it       Log On

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Question 1197980: 4. A construction worker drops a tool from the top of a building that is 455 feet tall. The function h = -16t² + 455 gives the height at any time t seconds. How much time does it take for the tool to hit the ground?
Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

Replace h with 0 since the object is at this height when it reaches the ground.

h+=+-16t%5E2+%2B+455

0+=+-16t%5E2+%2B+455

16t%5E2+=+455

t%5E2+=+455%2F16

t%5E2+=+28.4375

t+=+sqrt%2828.4375%29

t+=+5.33268


Answer: Approximately 5.33268 seconds