Question

Please help with this question!!!!

Answer 1

The m,maximum height is the vertex.  The (x, y)

x is the time

y is the height

h= -5t2 + 21t

find the vertex

-b/2a  is the x

-21/2(-5)  = -2.1 (-10) =  -2.1  is that man seconds its at its highest

now plug into

h= -5(2.1)^2 + 21(2.1) the answer is the max height