SOLUTION: If a stone is tossed from the top of a 290 meter building, the height of the stone as a function of time is given by h(t) = -9.8t^2 – 10t + 290, where t is in seconds, and height i

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Question 576648: If a stone is tossed from the top of a 290 meter building, the height of the stone as a function of time is given by h(t) = -9.8t^2 – 10t + 290, where t is in seconds, and height is in meters. After how many seconds will the stone hit the ground? Round to the nearest hundredth’s place; include units in your answer
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Start with:
h%28t%29+=+-9.8t%5E2-10t%2B290
When the stone hits the ground, h(t) = 0, so...
0+=+-9.8t%5E2-10t%2B290 Solve this quadratic equation using the quadratic formula: t+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F2a where: a = -09.8, b = -10, and c = 290.
t+=+%28-%28-10%29%2B-sqrt%28%28-b%29%5E2-4%28-9.8%29%28290%29%29%29%2F2%28-9.8%29
t+=+%2810%2B-sqrt%28100-%28-11368%29%29%29%2F%28-19.6%29
t+=+%2810%2B-sqrt%2812368%29%29%2F%28-19.6%29 Evaluate.
t+=+4.95secs. or t+=+-5.974secs. Discard the negative solution as the time is a positive quantity.
The stone will hit the ground after 4.95 seconds.