Ta có: `-3/4=-3/4`
`4/(-5)=-4/5`
Vì `-3>-4`
`=> -3/5 > -4/5`
\(\dfrac{-3}{4}\) và \(\dfrac{4}{-5}\)
\(\dfrac{-3}{4}=\dfrac{-3.5}{4.5}=\dfrac{-15}{20}\)
\(\dfrac{4}{-5}=\dfrac{-4}{5}=\dfrac{-4.4}{5.4}=\dfrac{-16}{20}\)
Vì \(\dfrac{-15}{20}>\dfrac{-16}{20}\) nên \(\dfrac{-3}{4}>\dfrac{4}{-5}\)