Answer:
1.74 second long after it was thrown does it hit the ground.
Step-by-step explanation:
Given : A football is thrown with an initial upward velocity of 25 feet per second from a height of 5 feet above the ground. The equation models the height in feet t seconds after it is thrown.
To find : How long after it was thrown does it hit the ground?
Solution :
The equation model is
After the ball passes its maximum height, it comes down and hits the ground.
i.e. h=0
So,
Solve by quadratic formula of equation is
Here, a=-16 , b=25 and c=5
We reject t=-0.179.
Therefore, 1.74 second long after it was thrown does it hit the ground.