I'm doing a project with a catapult, and basically I only have the x component.

I also have the mass of the projectile, x as a distance, y as the max height, angle of projection, total air time and the max potential/kinetic energy, but i don't think those matter that much.

I know the formula for the x component when knowing the velocity for the equation is Vx = Vcos?, but my question is

What's the formula to find velocity with the x component?

thanks in advance.