How do I figure out the velocity and starting height?

Question

The function H(t)=-16t^2+64t+12 shows the height H(t), in feet, of a baseball after t seconds.

I know the maximum height is 76 and that it takes 2 seconds for the ball to reach that height

How do I find the velocity (speed) of the ball and the starting height of the ball?

When would the baseball hit the ground?

Answer 1

The velocity of the ball will be constantly changing and will depend on t

at the starting point t=0 so just substitute 0 for t to get your answer

When the ball hits the ground the height is 0

so solve -16t^2 +64t +12= 0