Factor mn+5m-3n-15.
\(mn+5m-3n-15=\boxed{m}\cdot n+\boxed{m}\cdot5\boxed{-3}\cdot n\boxed{-3}\cdot5\\\\=\boxed{m}(n+5)\boxed{-3}(n+5)=\boxed{\boxed{(n+5)(m-3)}}\)
mn + 5m - 3n - 15(m - 3)(n + 5)
