1: \(-\dfrac{1}{2}< \dfrac{x}{18}< \dfrac{-1}{3}\)
=>\(-\dfrac{9}{18}< \dfrac{x}{18}< -\dfrac{6}{18}\)
=>-9<x<-6
2: \(\dfrac{4}{7}x-\dfrac{2}{4}=\dfrac{1}{5}\)
=>\(\dfrac{4}{7}x=\dfrac{1}{5}+\dfrac{2}{4}=\dfrac{7}{10}\)
=>\(x=\dfrac{7}{10}:\dfrac{4}{7}=\dfrac{49}{40}\)
3: \(-\dfrac{2}{5}+\dfrac{4}{5}x=\dfrac{3}{5}\)
=>\(\dfrac{4}{5}x=\dfrac{3}{5}+\dfrac{2}{5}=\dfrac{5}{5}=1\)
=>\(x=1:\dfrac{4}{5}=\dfrac{5}{4}\)
4: \(-\dfrac{3}{6}-\dfrac{4}{7}:x=-2\)
=>\(\dfrac{4}{7}:x=-\dfrac{3}{6}+2=2-\dfrac{1}{2}=\dfrac{3}{2}\)
=>\(x=\dfrac{4}{7}:\dfrac{3}{2}=\dfrac{4}{7}\cdot\dfrac{2}{3}=\dfrac{8}{21}\)
5: \(\dfrac{2}{5}+\dfrac{3}{4}:x=-\dfrac{1}{2}\)
=>\(\dfrac{3}{4}:x=-\dfrac{1}{2}-\dfrac{2}{5}=\dfrac{-9}{10}\)
=>\(x=-\dfrac{3}{4}:\dfrac{9}{10}=-\dfrac{3}{4}\cdot\dfrac{10}{9}=\dfrac{-30}{36}=-\dfrac{5}{6}\)
9: \(\dfrac{5}{7}-\dfrac{2}{3}x=\dfrac{4}{5}\)
=>\(\dfrac{2}{3}x=\dfrac{5}{7}-\dfrac{4}{5}=\dfrac{-3}{35}\)
=>\(x=-\dfrac{3}{35}:\dfrac{2}{3}=\dfrac{-9}{70}\)