# How do you write inverse variation equations given y=7 when x=4?

If $y$ is inversely proportional to $x$, then $y = \frac{k}{x}$ for some constant $k$. If $y = 7$ when $x = 4$, then $k = x \cdot y = 28$ so the inverse variation equation you are after is $y = \frac{28}{x}$.