\(\dfrac{-3}{4}+\dfrac{2}{7}+\dfrac{-1}{4}+\dfrac{3}{5}+\dfrac{5}{7}\)
=\(\left(\dfrac{-3}{4}+\dfrac{-1}{4}\right)+\left(\dfrac{2}{7}+\dfrac{5}{7}\right)+\dfrac{3}{5}\)
=-1+1+\(\dfrac{3}{5}=\dfrac{3}{5}\)
\(\dfrac{-3}{4}+\dfrac{2}{7}+\left(-\dfrac{1}{4}\right)+\dfrac{3}{5}+\dfrac{5}{7}\\ =\left(-\dfrac{3}{4}-\dfrac{1}{4}\right)+\left(\dfrac{2}{7}+\dfrac{5}{7}\right)+\dfrac{3}{5}\\ =-1+1+\dfrac{3}{5}\\ =\dfrac{3}{5}\)
\(\dfrac{-3}{4}+\dfrac{2}{7}+\dfrac{-1}{4}+\dfrac{3}{5}+\dfrac{5}{7}\)
\(=\left(\dfrac{-3}{4}+\dfrac{-1}{4}\right)+\left(\dfrac{2}{7}+\dfrac{5}{7}\right)+\dfrac{3}{5}\)
\(=\left(-1\right)+1+\dfrac{3}{5}\)
\(=0+\dfrac{3}{5}\)
\(=\dfrac{3}{5}\)
\(\dfrac{-3}{4}+\dfrac{2}{7}+\dfrac{-1}{4}+\dfrac{3}{5}+\dfrac{5}{7}\)
\(=\left(\dfrac{-3}{4}+\dfrac{-1}{4}\right)+\left(\dfrac{2}{7}+\dfrac{5}{7}\right)+\dfrac{3}{5}\)
\(=-1+1+\dfrac{3}{5}\)
\(=0+\dfrac{3}{5}=\dfrac{3}{5}\)
