An object is thrown upward from the top of an 80ft tower. The height h of the object after t seconds is represented by the quadratic equation h=-16t^2+64t+80

Question

After how many seconds will the object hit the ground

Answer 1

To find when the object hits the ground, we need to solve for h=0 in the equation h=-16t^2+64t+80:

-16t^2 + 64t + 80 = 0

Dividing by -16 to simplify:

t^2 - 4t - 5 = 0

Now, this quadratic equation can be factored as:

(t-5)(t+1) = 0

So the solutions are t=5 and t=-1. Since time cannot be negative, the object will hit the ground after 5 seconds.