Asoccer ball is kicked from 3 feet above the ground. the height, h, in feet of the ball after t seconds is given by the function h=-16t^2+64t+3
find the time it takes for the ball to return back to ground level.
find the maximum height rescued by the ball.

Here's our equation.



We want to find out when it returns to ground level (h = 0)

To find this out, we can plug in 0 and solve for t.





So the ball will return to the ground at the positive value of  seconds.

What about the vertex? Simple! Since all parabolas are symmetrical, we can just take the average between our two answers from above to find t at the vertex and then plug it in to find h!