\(a,\dfrac{1}{14}:x=-\dfrac{3}{35}\\ x=\dfrac{1}{14}:\left(-\dfrac{3}{35}\right)\\ x=\dfrac{1}{14}.\dfrac{-35}{3}\\ x=-\dfrac{5}{6}\\ ---\\ b,2\dfrac{1}{5}x-\dfrac{1}{3}x=-\dfrac{56}{45}\\ \left(\dfrac{11}{5}-\dfrac{1}{3}\right)x=-\dfrac{56}{45}\\ \dfrac{28}{15}x=-\dfrac{56}{45}\\ x=\dfrac{-56}{45}:\dfrac{28}{15}=\dfrac{-56}{45}.\dfrac{15}{28}\\ x=\dfrac{-2}{3}\)
\(c,\left(x+\dfrac{4}{7}\right)\left(x-\dfrac{8}{9}\right)=0\\\Leftrightarrow \left[{}\begin{matrix}x+\dfrac{4}{7}=0\\x-\dfrac{8}{9}=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{4}{7}\\x=\dfrac{8}{9}\end{matrix}\right.\\ ---\\ d,\left(3x-2\right)\left(2x-\dfrac{2}{3}\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}3x-2=0\\2x-\dfrac{2}{3}=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}3x=2\\2x=\dfrac{2}{3}\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{2}{3}\\x=\dfrac{1}{3}\end{matrix}\right.\)
