[tex] \frac{x}{y} = \frac{3}{5} [/tex]
[tex] \frac{3x - y}{x + y} = [/tex]
[tex]x = \frac{3y}{4} [/tex]
[tex] \frac{ \frac{9y}{4} - y}{ \frac{3y}{4} + y} [/tex]
[tex] \frac{ \frac{5y}{4} }{ \frac{7y}{4} } = [/tex]
[tex] \frac{5y}{4} \div \frac{7y}{4} = \frac{5y}{4} \times \frac{4}{7y} [/tex]
[tex] = \frac{5}{7} [/tex]
