Question

A(t)=-16t^2+120t what is the maximum height of the arrow

Answer 1

A(t)=-16t^2+120t
= +120t - (4t)^2
= 225 -225 +2(4t)*15 -(4t)^2
= 225 - (15-4t)^2

Answer 2

hope u can do from here ...
max value of A(t) is 225

Answer 3

I think, that is the downward parabola, so that the maximum is the vertex of it. And we have formula to find out the vertex. It is x-coordinate = \(\dfrac{-b}{2a}\) then plug back to the original equation to find A that is the y-coordinate of the vertex.