Beginning Algebra With Applications, Chapter 5, 5.4, Section 5.4, Problem 24

Using the point slope formula, find the equation of the line that passes through the point whose coordinates are $(0,0)$ and has slope of $\displaystyle \frac{-1}{5}$


$
\begin{equation}
\begin{aligned}

(x_1, y_1) =& (0,0)
&& \text{Let $(x_1, y_1)$ be the given point}
\\
m =& \frac{-1}{5}
&& \text{$m$ is the given slope}
\\
y - y_1 =& m(x- x_1)
&& \text{Point slope formula}
\\
y - 0 =& \frac{-1}{5} (x-0)
&& \text{Substitute $$ for $x$, $$ for $y$ and } \frac{-1}{5} \text{ for $m$}
\\
y =& \frac{-1}{5}x
&& \text{Rewrite the equation in the form } y = mx+b

\end{aligned}
\end{equation}
$