## Precalculus (6th Edition) Blitzer

$S 80^{\circ} W$
The trigonometric ratios are as follows: $\sin \theta= \dfrac{opposite}{hypotenuse}$ ; $\cos \theta= \dfrac{Adjacent}{hypotenuse}$ and $\tan \theta= \dfrac{Opposite}{Adjacent}$ The angle is from the vertical axis $S$ to the line joining the point $C$. So, our required answer is: $S 80^{\circ} W$