Answer
$-\frac{\sqrt 2}{2}$
Work Step by Step
$r=\sqrt {x^{2}+y^{2}}=\sqrt {(-3)^{2}+(-3)^{2}}=3\sqrt 2$
$\sin\theta=\frac{y}{r}=\frac{-3}{3\sqrt 2}=-\frac{1}{\sqrt 2}=-\frac{\sqrt 2}{2}$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.