Problema 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) = -9.8t2 – 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 provided by our tutors

h(t) = -9.8t^2 - 10t + 290

Set h(t) to zero (since when height = 0, it'll hit the ground):

0 = -9.8t^2 - 10t + 290

We apply the "quadratic formula".

t = {-5.973915726623492, 4.953507563358185}

We can toss out the negative solution leaving:

t = 4.953507563358185 seconds.