\(\dfrac{3}{10}\left(\dfrac{-4}{9}+\dfrac{2}{5}\right)-\dfrac{3}{10}\left(\dfrac{5}{9}+\dfrac{-3}{5}\right)\\ =\dfrac{3}{10}\left[\left(\dfrac{-4}{9}+\dfrac{2}{5}\right)-\left(\dfrac{5}{9}+\dfrac{-3}{5}\right)\right]\\ =\dfrac{3}{10}\left(\dfrac{-4}{9}+\dfrac{2}{5}-\dfrac{5}{9}-\dfrac{-3}{5}\right)\\ =\dfrac{3}{10}\left[\left(\dfrac{-4}{9}-\dfrac{5}{9}\right)+\left(\dfrac{2}{5}-\dfrac{-3}{5}\right)\right]\\ =\dfrac{3}{10}\left(\dfrac{-9}{9}+\dfrac{5}{5}\right)\\ =\dfrac{3}{10}\left(-1+1\right)\\ =\dfrac{3}{10}.0\\=0 \)
\(\dfrac{3}{10}.\left(-\dfrac{4}{9}+\dfrac{2}{5}\right)-\dfrac{3}{10}.\left(\dfrac{5}{9}-\dfrac{3}{5}\right)\\ =\dfrac{3}{10}.\left(-\dfrac{4}{9}+\dfrac{2}{5}-\dfrac{5}{9}+\dfrac{3}{5}\right)\\ =\dfrac{3}{10}.\left(1-1\right)\\ =\dfrac{3}{10}.0\\ =0\)
\(\dfrac{3}{10}.\left(-\dfrac{4}{9}+\dfrac{2}{5}\right)-\dfrac{3}{10}\left(\dfrac{5}{9}+\dfrac{-3}{5}\right)\)
\(=\dfrac{3}{10}.\left[\left(-\dfrac{4}{9}-\dfrac{5}{9}\right)+\left(\dfrac{2}{5}+\dfrac{3}{5}\right)\right]\)
\(=\dfrac{3}{10}.\left(-1+1\right)\)
\(=\dfrac{3}{10}.0=0\)
`= 3/10 (-4/9 + 2/5 + 3/5 - 5/9)`
`= 3/10(-4/9 - 5/9 + 2/5 + 3/5)`
`= 3/10 . 0`
`= 0`