Given:
[tex]\begin{gathered} \tan 30=\frac{AB}{BC} \\ \frac{1}{\sqrt[]{3}}=\frac{AB}{8} \\ AB=\frac{8}{\sqrt[]{3}} \\ AB=\frac{8}{3}\sqrt[]{3} \end{gathered}[/tex]Height of the right triangle is
[tex]\begin{gathered} AB=\frac{8}{3}\sqrt[]{3}\text{ units} \\ AB=4.6189\text{ units} \end{gathered}[/tex]