Answer:
Step-by-step explanation:
REcall that all the points of the unit circle have the following coordinates [tex](\cos \theta, \sin \theta)[/tex], where theta is the angle in standard position (that is, with the terminal side on the given point and the initial side on the x-axis).
Then in this case we have that [tex]\cos\theta = \frac{1}{\sqrt[]{10}}, \sin \theta =\frac{-3}{\sqrt[]{10}}[/tex].
Recall that [tex]\tan \theta = \frac{\sin \theta}{\cos \theta} = \frac{\frac{-3}{\sqrt[]{10}}}{\frac{1}{\sqrt[]{10}}} = -3[/tex]
