Hi, I'm having a very difficult time figuring out how to find the velocity needed to reach a point for a projectile (shot from a cannon) to reach a point with air resistance.

time step is constant: 0.02

air resistance is constant: 1 / (1 + 0.02 * drag), where drag is a constant: 2

gravity is constant: -9.81

initial velocity is: 7, 20

mass is constant: 1

integration is like so:

velocity += gravity * 0.02

velocity *= airResistance

position += velocity * 0.02

I'm not much of a math guy, any help would be greatly appreciated