Jeffrey K. answered • 09/24/20

Together, we build an iron base in mathematics and physics

Ed, here's the approach:

The term "geometric vectors" is unclear, so let's do this with algebra.

The equation for a projectile's range is: R = v_{0}^{2} sin 2θx tanθ) - [g / (2v_{0}cosθ)^{2}] x^{2} . . . . . which is the equation of a parabola

We need to find the launch angle θ

It is launched at y = 12 m and lands at y = 4 m.

Taking the initial site as our origin, then it lands at y = -8 and x = 200 m.

Plug into the above equation: -8 = 200 tanθ - [9.8 / 2(15) cosθ]^{2} (200)^{2}