When the ball hit the ground, the height will be equal to "0".
h=0
Then:
-16t²+30t+6=0
we have to solve this square equation:
t=[-30⁺₋√(900+384)] / (-32)
t=(-30⁺₋√1284)/(-32)
we have two solutions:
t₁=(-30-√1284)/(-32)=2.06
t₂=(-30+√1284)/(-32)=-0.18 This solution is not valid.
Answer: 2.06 seconds.
t