\(=\dfrac{6}{13}.\left(-1\right).\dfrac{5}{9}-\dfrac{5}{9}.\dfrac{7}{13}\\ =\dfrac{5}{9}.\left(-\dfrac{6}{13}-\dfrac{7}{13}\right)\\ =\dfrac{5}{9}.\left(-\dfrac{13}{13}\right)\\ =\dfrac{5}{9}.\left(-1\right)\\ =-\dfrac{5}{9}\)
\(=\dfrac{-5}{9}.\left(\dfrac{6}{13}+\dfrac{7}{13}\right)\)
\(=\dfrac{-5}{9}.1\)
\(=\dfrac{-5}{9}\)
`6/13 . (-5)/9 - 5/9 . 7/13`
`= 6/13 . (-1) . 5/9 - 5/9 . 7/13`
`= (-6)/13 . 5/9 - 5/9 . 7/13`
`= 5/9 . ( (-6)/13 - 7/13)`
`= 5/9 . (-13)/13`
`= 5/9 . (-1)`
`= (-5)/9`
`Yiuby`
