A ball is thrown from a height of

130
feet with an initial downward velocity of
6/fts
. The ball's height
h
(in feet) after
t
seconds is given by the following.
=h−130−6t16t2
How long after the ball is thrown does it hit the ground?

1 answer

Your equation should have been

h = -16t^2 - 6t + 130

When it hits the ground, h = 0
so,
16t^2 + 6t - 130 = 0
I would use the quadratic equation formula to solve for t
(to be able to handle this topic, you MUST know that formula)
make sure to reject any negative value of t.