Let d be the distance of the point of intersection of the lines \(\rm \frac{x+6}{3}=\frac{y}{2}=\frac{z+1}{1}\) and \(\rm \frac{x-7}{4}=\frac{y-9}{3}=\frac{z-4}{2}\) from the point (7, 8, 9). Then d² + 6 is equal to :