\[xy + x = 15\]
\[x \cdot (y + 1) = 15\]
\[x = \frac{15}{y + 1} = \frac{15}{y} + 15\]
\[x = 5;\ \ y = 18;\]
\[x = 3;\ \ y = 20;\]
\[x = 15;\ \ y = 16.\]