Answer
$y=-\frac{4}{5}x$
Work Step by Step
The given line has a slope of $-\frac{4}{5}$ and a y-intercept of $(0,0)$. We can write this line in the slope-intercept form $y=mx+b$ (where m is the slope of the line, and the point $(0,b)$ is the y-intercept).
In this case, $m=-\frac{4}{5}$ and $b=0$.
Therefore, $y=-\frac{4}{5}x+0=-\frac{4}{5}x$.