$\angle AOP+\angle AON={90}^{\circ }$ (as ON is perpendicular to POQ)
Given, $\angle AOP={60}^{\circ }$
$⟹\angle AON={90}^{\circ }-{60}^{\circ }$​
$\angle AON={30}^{\circ }$
By Laws of reflection,
$\angle AON=\angle BON=x$
Thus, $x={30}^{\circ }$

Laws of reflection are valid for all kinds of reflection, be it regular or irregular.

In case of irregular reflection of parallel rays, the reflected rays are not parallel. If we consider the individual rays, we see that the laws of reflection apply to each of them.

According to the laws of reflection,
The angle of incidence is equal to the angle of reflection.
Or,
Angle of incidence = Angle of reflection