Answer
See below.
Work Step by Step
From what we learned: $\sin(-45^\circ)=-\frac{1}{\sqrt2},\cos(-45^\circ)=\frac{1}{\sqrt2},\tan(-45^\circ)=\frac{\sin(-45^\circ)}{\cos(-45^\circ)}=\frac{-\frac{1}{\sqrt2}}{\frac{1}{\sqrt2}}=-1$, which is undefined
