Given that the x and y variables are proportional, then they satisfy the next relationship:
y = kx
where k is some constant.
Isolating k, we get:
k = y/x
Computing y/x with the values of the table:
[tex]\begin{gathered} k=\frac{y}{x} \\ k=\frac{6}{2}=\frac{9}{3}=\frac{15}{5}=\frac{18}{6}=3 \end{gathered}[/tex]
Therefore, the equation that relates x and y is:
y = 3x
