Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
h = - 16t2 - 32t + 320...?
h = - 16t2 - 32t + 320 gives the height of a ball, thrown downward from the top of a 320 foot building with an initial velocity of 32 feet per second.
Find the time in seconds that it takes for the ball to reach a height of 48 feet.
A. 5.243 seconds
B. 3.243 seconds
C. 5.583 seconds
D. 4.375 seconds
2 Answers
- s kLv 710 years agoFavorite Answer
48 = -16t^2 - 32t + 320
16t^2 + 32t - 272 = 0
t^2 + 2t - 17 = 0
t = (-2 ± √(4 + 68)) / 2
t = (-2 ± √(72)) / 2
t = (-2 ± 6√2) / 2
t = -1 ± 3√2
As 3√2 > 1 and we only want positive solutions,
t = -1 + 3√2 ≈ 3.243 seconds.
- ?Lv 45 years ago
provided that city regulation prohibits throwing ordinances from rooftops, you would be arrested by applying the time it lands on the floor, except the ball hits the law enforcement officials(s) wherein case you would be charged with attack, trespassing (except you very own the development) and mischief. The time is the least of your concerns.
