$$\frac{ 1 }{ 7x } + \frac{ 1 }{ 6y } =3, \frac{ 1 }{ 3x } - \frac{ 1 }{ 3y } =5$$
$x=\frac{13}{231}\approx 0.056277056$
$y=\frac{13}{36}\approx 0.361111111$
