Newton's First Law:

Newton's Second Law:

For constant net force and motion beginning at t=0: a_x= ΣF_x/m a_y= ΣF_y/m.

Then the equations of motion, or the kinematic equations, are:

v_x(t) = v_x(0) + a_x t

x(t) = x(0) + v_x(0) t +½ a_x t²

v_x(t)² = v_x(0)² + 2 a_x [x(t) - x(0)]

x(t) = x(0) +½ [v(0) + v_x(t)] t

and similarly for the y-direction.

IMPORTANT: Keep the x-component and y-component equations separate! The only attribute common to both sets of equations is the time.