Aball is shot upward from a slingshot at a velocity of 15 m/s the height of the ball after t seconds is given by h(t)=10+ 5t+1/4 t^2 predicted the instantaneous velocity after eight seconds

The instantaneous velocity after eight seconds is 9 m/s

Step-by-step explanation:

Given as :

The ball shot upward with velocity of 15 m/s

The height of the ball after t sec is given as h(t) =

Now, The instantaneous velocity after 8 sec =

Or, The instantaneous velocity =

or, The instantaneous velocity =

Now at t = 8 sec

The instantaneous velocity = 5 + 4 = 9 m/s

Hence The instantaneous velocity of ball at t = 8 sec , is 9 m/s  Answer

14

step-by-step explanation:

14 x 3 = 42