Question

5/x-7/y= -9
solve for y and x​

Answer 1

$\: \: \: \: \: \: \huge \tt \frac{5}{x} - \frac{7}{y} = (- 9) \\ \\ \sf= > \: \: \: \: \: \: \: \frac{5y - 7x}{xy} = ( - 9) \\ \\ \sf = > \: \: \: \: \: \: \: 5y - 7x = ( - 1)(9xy) \\ \\ \sf = > \: \: \: \: \: \: \frac{5y - 7x}{ - 1} = 9xy \\ \\ \sf = > \: \: \: \: \: \: 7x - 5y = 9xy$

From this,

$\large \bf x = \red{\frac{9xy + 5y}{7}} \\ \\ \\ \large \bf y = { \bigg(}\frac{9xy - 7x}{ - 5} { \bigg)} = \red{\frac{7x - 9xy}{5} }$