Solve the following math problem step by step. The last line of your response should be of the form Answer: \boxed{$Answer} where $Answer is the answer to the problem.

<image>In $\Delta G H J$, $H P=5 x-16$, $P J=3 x+8$, $m \angle G J N=6 y-3$, $m \angle N J H=4 y+23$ and $m \angle H M G=4 z+14$. Find $m∠GJH$ if $\overline{JN}$ is an angle bisector.