When the ball will hit the ground, the height will be zero. So we need to replace 
with 0 in our equation, and solve for 
:
To solve this equation we are going to use the quadratic formula:
.
From our height equation, we can infer that
, 
, and 
. So lets replace those values in our quadratic formula to find
or 
or 
Since time cannot be negative, is the solution of our equation.
We can conclude that the ball will hit the ground after 2.71 seconds.
To solve this equation we are going to use the quadratic formula:
From our height equation, we can infer that
Since time cannot be negative,
We can conclude that the ball will hit the ground after 2.71 seconds.