calculate when ball is at a specific height

Question

given maximum height and when it hits the ground

maximum height = 14m

hitting the ground again = 6s

determine a quadratic equation in the form of ax^2+bx+ c = 0 that can be used to calculate when ball is at a height of 2m

Answer 1

If it takes 6 sec to hit the ground; the highest point is (t^2+t)/2*9.81=206.01m.

So at 2m; the ball dropped 4m so (t^2+t)/2*9.81=4m

t=.532sec

This is all into dropping.

Another formula is: dt=V1*t+.5*at^2.

a=9.81

V1=?

t=?

dt=up/down