Question

A ball is thrown vertically upwards. After t seconds, his height (in feet) is given by the function h(t)=104t-16t^2. After how long will it reach its maximum height?

Answer 1

$104t-16t^2=-16(t^2-6.5t+10.5625-10.5625)=-16(t-3.25)+169$

At t= 2.5 seconds it will reach the maximum height 169 m..