\(\left(\dfrac{-5}{28}+1,75+\dfrac{8}{35}\right)\):\(\left(\dfrac{-39}{20}\right)\)

=\(\left(\dfrac{-5}{28}+\dfrac{7}{4}+\dfrac{8}{35}\right):\left(\dfrac{-39}{20}\right)\)

=\(\left(\dfrac{11}{7}+\dfrac{8}{35}\right):\left(\dfrac{-39}{20}\right)\)

=\(\dfrac{9}{5}:\left(\dfrac{-39}{20}\right)\)

=\(\dfrac{9.\left(-20\right)}{5.39}\)

=\(\dfrac{3.\left(-4\right)}{1.13}\)

=\(\dfrac{-12}{13}\)