Let $A ( 6,8 ) , B ( 10 \cos \alpha , - 10 \sin \alpha )$ and $C ( - 10 \sin \alpha , 10 \cos \alpha )$, be the vertices of a triangle. If $L ( a , 9 )$ and $G ( h , k )$ be its orthocenter and centroid respectively, then $( 5 a - 3 h + 6 k + 100 \sin 2 \alpha )$ is equal to $\_\_\_\_$