Giải:
a)\(\dfrac{3}{4}x-\dfrac{1}{3}=\dfrac{-5}{6}\)
\(\dfrac{3}{4}x=\dfrac{-5}{6}+\dfrac{1}{3}\)
\(\dfrac{3}{4}x=\dfrac{-1}{2}\)
\(x=\dfrac{-1}{2}:\dfrac{3}{4}\)
\(x=\dfrac{-2}{3}\)
b)\(\left(2\dfrac{4}{5}x-0,2\right):\dfrac{4}{5}=\dfrac{7}{8}\)
\(\dfrac{14}{5}x-\dfrac{1}{5}=\dfrac{7}{8}.\dfrac{4}{5}\)
\(\dfrac{14}{5}x-\dfrac{1}{5}=\dfrac{7}{10}\)
\(\dfrac{14}{5}x=\dfrac{7}{10}+\dfrac{1}{5}\)
\(\dfrac{14}{5}x=\dfrac{9}{10}\)
\(x=\dfrac{9}{10}:\dfrac{14}{5}\)
\(x=\dfrac{9}{28}\)
c) \(\dfrac{1}{4}+\dfrac{1}{3}:\left|2x-1\right|=\dfrac{11}{12}\)
\(\dfrac{1}{3}:\left|2x-1\right|=\dfrac{11}{12}-\dfrac{1}{4}\)
\(\dfrac{1}{3}:\left|2x-1\right|=\dfrac{2}{3}\)
\(\left|2x-1\right|=\dfrac{1}{3}:\dfrac{2}{3}\)
\(\left|2x-1\right|=\dfrac{1}{2}\)
⇒2x-1=\(\dfrac{1}{2}\) hoặc 2x-1=\(\dfrac{-1}{2}\)
x=\(\dfrac{3}{4}\) hoặc x=\(\dfrac{1}{4}\)
câu a nha \(\dfrac{3}{4}x-\dfrac{1}{3}=-\dfrac{5}{6}\)
\(\dfrac{3}{4}x=-\dfrac{5}{6}+\dfrac{1}{3}\)
\(\dfrac{3}{4}x=-\dfrac{3}{6}\)
\(x=-\dfrac{3}{6}:\dfrac{3}{4}\)
\(x=-\dfrac{6}{4}.\dfrac{4}{3}\)
\(x=-\dfrac{24}{12}=-2\)