We have to apply the Thales theorem, where the proportions between sides of similar triangles are equal.
We can write the ratio between the opposite side to N and the adyacent side to N.
Then, we can write:
[tex]\begin{gathered} \frac{k}{3}=\frac{8}{3+3}=\frac{8}{6} \\ k=3\cdot\frac{8}{6}=\frac{24}{6}=4 \end{gathered}[/tex]
The value of k is k=4.
