To answer this question we will use the following formula for the angle corresponding to a complex number z:
[tex]\theta=\arctan (\frac{\operatorname{Im}(z)}{\operatorname{Re}(z)})\text{.}[/tex]
In this case:
[tex]\begin{gathered} \operatorname{Re}(z)=8, \\ \operatorname{Im}(z)=-9. \end{gathered}[/tex]
Therefore:
[tex]\theta=\arctan (\frac{-9}{8})\approx-0.844.[/tex]
Answer:
[tex]\theta=-0.844.[/tex]
