we have that
The constant of proportionality k is equal to [tex]\frac{7}{10}[/tex]
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form [tex]\frac{y}{x}=k[/tex] or [tex]y=kx[/tex]
so
substitute the value of k in the formula
[tex]\frac{y}{x}=\frac{7}{10}[/tex]
therefore
the answer is
[tex]\frac{y}{x}=\frac{7}{10}[/tex]
