Question 378930
You didn't give the info, so I'll assume this is on the Earth and use
h(t) = -4.9t^2 + vt, t in seconds, h in meters
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h(t) = -16t^2 + 2.3t
Find t for h(t) = -3.5 meters
-3.5 = -4.9t^2 + 2.3t
-4.9t^2 + 2.3t + 3.5 = 0
*[invoke solve_quadratic_equation -4.9,2.3,3.5]
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t = 1.1118 seconds (Ignore the negative solution)
velocity = h'(t) = -9.8t + 2.3
h'(1.1118) = -8.59564 m/sec at impact (negative = going down)