Answer
0
Work Step by Step
We can find the tangent of coterminal angle that belongs to [$0^{\circ}$,$360^{\circ}$) for convenience.
$\tan(1800^{\circ})= $
$\tan(1800^{\circ}-5\cdot360^{\circ})=\tan 0^{\circ}$
The terminal side of $0^{\circ}$ angle passes through (1,0). So $x=1,y=0$ and $r=1$.
$\tan 0^{\circ}=\frac{y}{x}=\frac{0}{1}=0$
