\(\frac{x}{y}=\frac{3}{5}=\frac{-3}{-5}\)
\(\frac{x}{y}=\frac{3}{5}\)
\(\Rightarrow\hept{\begin{cases}\frac{x}{y}=\frac{3}{5}\\\frac{x}{y}=\frac{-3}{-5}\end{cases}}\)
\(\hept{\begin{cases}\frac{x}{y}=\frac{3}{5}\\\frac{x}{y}=\frac{-3}{-5}\end{cases}}\)