The maximum height is:
hmax = v0² sin² α / 2 g
The horizontal range is: x = v0² sin 2 α / g
So we are given that:
x = 14.5 hmax
v0² sin 2 α / g
= 14.5 v0² sin² α / 2 g
7.25 sin² α = 2 sin α cos α
7.25 sin α = 2 cos α
7.25 tan α = 2
tan α = 0.27586
α = tan^(-1) 0.27586
α = 15.42°
The angle of projection is 15.42°
