Find the domain and range of the function, $f(x,y) = \sqrt{x+y}$ and sketch the domain in the xy-plane. I have found the domain to be $y \geq -x$.
I have found the range to be $z \geq 0$, or $[ 0, \infty )$.
I'm not sure how to sketch the domain in the xy-plane. I figured it would be a straight line through $(0,0)$ with $-1$ slope, and the values in the domain would be everything above that line, but I seem to be wrong.

This is not an answer. I just needed the attach picture feature to show the domain of the function, which is the hatched region.
Hope it helps
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