68.0k views
2 votes
a high school football player is practicing his frield goals kicks. The equation h=-9t²+45t where t is the number of seconds gone by and h is the height of the ball in feet. how long does it take for the ball to hit the ground ​

User Rcoup
by
8.2k points

1 Answer

5 votes

h = -9t^2 + 45t

First, let's factor the equation.

h = -9t(t - 5)

Let's set both terms equal to zero.

-9t = 0

Divide both sides by -9

t = 0

t - 5 = 0

Add 5 to both sides.

t = 5

We know that it took more than 0 second sto hit the ground, therefore, the only answer that makes sense is t = 5

It took 5 seconds for the football to hit the ground.

User Nianyi Wang
by
7.0k points