I'm asked to find the domain and range of this function:

$\displaystyle x = -|y|$

Since $\displaystyle |y| \geq 0$ then $\displaystyle -|y| \leq 0$. So, I think the range of this function be $\displaystyle (-\infty,0]$.

I'm not sure how to find the domain though. Would the domain just be all reals? e.g. $\displaystyle (-\infty,\infty)$