You throw a ball upward. its height h in feet after t seconds can be modeled by the function h=-16t^2+30t+6. after how many seconds will it hit the ground

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