A ball is thrown from a height of 255 feet with an initial downward velocity of 21/fts. The ball's height h (in feet) after t seconds is given by the following. =h−255−21t16t2
How long after the ball is thrown does it hit the ground?
Round your answer(s) to the nearest hundredth.

6, 10

9, -13

12, -21

18, -23

step-by-step explanation:

you just add 6 to the x-coordinate and subtract 10 from the y-coordinate.

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

i believe the answer is c.

-81 -56 -27 0 81

step-by-step explanation: