b: =>2/3-x=11/7-11/4=-33/28
=>x=155/84
c: =>1/4:x=2/5-3/4=8/20-15/20=-7/20
=>x=-5/7
a) \(x+\dfrac{3}{5}=\dfrac{1}{4}\)
\(x=\dfrac{1}{4}-\dfrac{3}{5}\)
\(x=\dfrac{5}{20}-\dfrac{12}{20}=-\dfrac{7}{20}\)
b) \(\dfrac{2}{3}-x=1\dfrac{4}{7}-2\dfrac{3}{4}\)
\(\dfrac{2}{3}-x=\dfrac{11}{7}-\dfrac{11}{4}\)
\(\dfrac{2}{3}-x=-\dfrac{33}{28}\)
\(x=\dfrac{2}{3}-\left(-\dfrac{33}{28}\right)\)
\(x=\dfrac{155}{84}\)
c) \(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
\(\dfrac{1}{4}:x=\dfrac{2}{5}-\dfrac{3}{4}\)
\(\dfrac{1}{4}:x=-\dfrac{7}{20}\)
\(x=\dfrac{1}{4}:\left(-\dfrac{7}{20}\right)\)
\(x=-\dfrac{5}{7}\)
