Help with math problems

Question

A ball is thrown vertically upward. After t seconds, its height, h (in feet) is given by the function h(𝑡) = 88𝑡 − 16𝑡2. After how long will the ball reach its maximum height?

Answer 1

h(t) = -16t² + 88t

 

Maximum height occurs at the vertex of the height-vs.-time parabola, which is at

 

t = -88/[2(-16)] seconds = ? sec