A ball is thrown straight up from a rooftop 320 feet high. The formula below describes the​ ball's height above the​ ground, h, in​ feet, t seconds after it was thrown. The ball misses the rooftop on its way down and eventually strikes the ground. How long will it take for the ball to hit the​ ground? Use this information to provide tick marks with appropriate numbers along the horizontal axis in the figure shown. h=-16t^2+16t+320
The ball hits the ground after seconds

28 seconds

3; 9 is 8 to -4

step-by-step explanation:

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!