Answer
$\sin\theta=\frac{y}{r}=\frac{-4}{2\sqrt 5}=\frac{-2\sqrt 5}{5}$
$\cos\theta=\frac{x}{r}=\frac{2}{2\sqrt 5}=\frac{\sqrt 5}{5}$
$\tan\theta=\frac{y}{x}=\frac{-4}{2}=-2$
$\csc\theta=\frac{1}{\sin\theta}=-\frac{\sqrt 5}{2}$
$\sec\theta=\frac{1}{\cos\theta}=\sqrt 5$
$\cot\theta=\frac{1}{\tan\theta}=-\frac{1}{2}$
Work Step by Step
$x=2$
$y=-4$
$r=\sqrt {(2)^{2}+(-4)^{2}}=\sqrt {4+16}=\sqrt {20}= 2\sqrt 5$