Answer
$\tan 450^{\circ}=undefined$
Work Step by Step
1. What we know about 450 degree angle
$\theta=90^{\circ}$ (because it is a co-terminal angle and values of x and y will be the same)
$x=0$
$y=1$
$r=1$
2. Substitute in:
$\tan\theta=\frac{y}{x}=\frac{1}{0}=undefined$
