To find the phase angle of a wave equation given as y(x,t) = Acos(kx - wt), identify the term that represents the phase shift, which is typically denoted as φ. In the standard form of the wave equation, y(x,t) = Acos(kx - ωt + φ), φ indicates the phase angle. If φ is not explicitly included in the equation, it is assumed to be zero. Thus, the phase angle in this case is zero unless specified otherwise. Understanding this allows for accurate interpretation of wave behavior.