\(\left(-\dfrac{7}{5}+-\dfrac{3}{4}\right)\cdot\left(\dfrac{1}{2}+\dfrac{4}{5}\right)\)
\(=-\dfrac{43}{20}\cdot\dfrac{13}{10}\)
\(=-\dfrac{559}{200}\)
\(\left(\dfrac{-7}{5}+\dfrac{-3}{4}\right)\cdot\left(\dfrac{1}{2}+\dfrac{4}{5}\right)\)
\(=\left(\dfrac{-7.4}{5.4}+\dfrac{-3.5}{4.5}\right)\cdot\left(\dfrac{1.5}{2.5}+\dfrac{4.2}{5.2}\right)\)
\(=\left(\dfrac{-28}{20}+\dfrac{-15}{20}\right)\cdot\left(\dfrac{5}{10}+\dfrac{8}{10}\right)\)
\(=\left(\dfrac{\left(-28\right)+\left(-15\right)}{20}\right)\cdot\left(\dfrac{5+8}{10}\right)\)
\(=\dfrac{-43}{20}\cdot\dfrac{13}{10}\)
\(=\dfrac{\left(-43\right).13}{20.10}\)
\(=\dfrac{-559}{200}\)
\(\left(\dfrac{-7}{5}+\dfrac{-3}{4}\right)\) . \(\left(\dfrac{1}{2}+\dfrac{4}{5}\right)\)
= \(\dfrac{-43}{20}\) . \(\dfrac{13}{10}\) = \(\dfrac{559}{200}\)