Question

Suppose you throw a ball straight up from the ground with a velocity of 256

Answer 1

Answer:

Below in bold.

Step-by-step explanation:

a. h after 4 seconds:

h = -16(4)^2 + 256(4)    

    = -256 + 1024

    =  768 ft

b.   When the height is 1008 ft

     1008 = -16t^2 + 256t

     16t^2 - 256t + 1008 = 0

      16(t^2 - 16t + 63) = 0

       16(t - 7)(t - 9) = 0

        t = 7, 9

      So it will take 7 seconds to rise to 1008 feet and and after 9 seconds        it will pass 1008 on the way down

     So the times are 7, 9 seconds.

c.  When the ball reaches the ground h = 0:

    -16t^2 + 256t = 0

    -16t(t - 16) = 0

      t - 16 = 0

      t = 16 seconds.