\(d,\Rightarrow\dfrac{14}{15}x=-\dfrac{2}{5}\Rightarrow x=-\dfrac{2}{5}\cdot\dfrac{15}{14}=-\dfrac{3}{7}\\ e,\Rightarrow\dfrac{29}{21}x=\dfrac{3}{10}\Rightarrow x=\dfrac{3}{10}\cdot\dfrac{21}{29}=\dfrac{63}{290}\)
\(d,\dfrac{1}{3}x+\dfrac{3}{5}x=-\dfrac{2}{5}\\ \Rightarrow\left(\dfrac{1}{3}+\dfrac{3}{5}\right)x=-\dfrac{2}{5}\\ \Rightarrow\dfrac{14}{15}x=-\dfrac{2}{5}\\ \Rightarrow x=-\dfrac{2}{5}:\dfrac{14}{15}\\ \Rightarrow x=-\dfrac{3}{7}\)
\(e,\dfrac{5}{7}x+\dfrac{2}{3}x=\dfrac{3}{10}\\ \Rightarrow\left(\dfrac{5}{7}+\dfrac{2}{3}\right).x=\dfrac{3}{10}\\ \Rightarrow\dfrac{29}{21}x=\dfrac{3}{10}\\ \Rightarrow x=\dfrac{3}{10}:\dfrac{29}{21}\\ \Rightarrow x=\dfrac{63}{290}\)
