Answer
Slope: $-1$
$y$-intercept: $-13$
Work Step by Step
The slope-intercept form of a linear equation of a non vertical line is $y=mx+b$, where $m$ is the slope and $b$ is the $y$-intercept.
We use this fact to find the slope and $y$-intercept of $y=-x-13$
We rewrite the equation: $y=-1x+(-13)$
Since $-1$ takes the place of $m$, it is the slope.
Since $-13$ takes the place of $b$, it is the $y$-intercept.
