Answer:
The bisector of an angle is a ray that separates the angle into two congruent angles.
As, PQ bisects [tex]\angle MPN[/tex]
then,
[tex]\angle MPQ \cong \angle QPN[/tex]
By the definition of congruent angle : An angle that have the same measure
[tex]m \angle MPQ = m\angle QPN[/tex]
As you can also see in the figure as shown below;
