12. Determine the equation of distance between the two ships

 

A person standing on top of the lighthouse observes two ships in the sea. He wanted to find an equation of the distance between the two ships. So, he plotted the position of two ships in the \((x,y)\) plane whose \(x\) - intercept and \(y\) - intercept are $\frac{2}{7}$ and $\frac{7}{8}$, respectively.

 

The equation of the distance between the two ships is