homework and exercises - Aerodynamic drag on a cannonball?

I'm trying to build a ballistics simulation where I shoot a cannonball. I want to allow for drag and am trying to work out the math to do so.

I can work the drag out using $F = C_d\times S\times V^2\times A/2$.

What I need to know is how to find the $x$ and $y$ parts of that. I use $V\cos(A)$ and $V\sin(A)$ to work out the $x$ and $y$ velocities. Can I just use this to find the $x$ and $y$ drag too?