[tex]\begin{gathered} 1)\ast\text{Idempotency property of }\cong \\ 2)\text{AM = MB }\cong\text{ }\ast\text{Definition of a bisector} \\ 3)\text{ triangle PMA }\cong\text{ triangle PMB }\ast\text{ SAS ( two sides and included angle)} \end{gathered}[/tex]
Hence,
[tex]PA\cong PB[/tex]
