baseball height

Question

a baseball is hit from ground level with an initial velocity of 160 ft per second, then its height is a function of time, given that s=16t²+160t. what is the maximum height reached by the ball

Answer 1

-b/(2a) = -160/(-32) = 5

-16(5^2) + 160(5) = (-16)(25) + 800 = 800 - 400 = 400