Graph $y = -2x-1$ by using the slope and $y$-intercept.
$y$-intercept:
$
\begin{equation}
\begin{aligned}
y =& -2x-1
&& \text{Given equation}
\\
y =& -2(0) -1
&& \text{To find the $y$-intercept, let } x = 0
\\
y =& -1
&&
\end{aligned}
\end{equation}
$
The $y$-intercept is $(0,-1)$
$
\begin{equation}
\begin{aligned}
m =& \frac{\text{change in } y}{\text{change in } x}
\\
\\
m =& \frac{-2}{1}
\\
\\
m =& -2
\end{aligned}
\end{equation}
$
Beginning at the $y$-intercept, move to the right 1 unit and then down 2 units.
$(1, -3)$ are the coordinates of a second point on the graph.
Draw a line through $(0,-1)$ and $(1, -3)$
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