Answer
$y=2x$
Work Step by Step
Since $y$ varies directly as $x,$ then it follows the model $y=kx.$ Solving for $k$ by substituting the given point, $
(1,2)
,$ results to
\begin{array}{l}\require{cancel}
y=kx
\\
2=k(1)
\\
2=k
.\end{array}
Hence, the direct variation equation is $
y=2x
.$
Using a table of values, the graph of $
y=2x
$ is shown.
