\(a,5\left(2x-3\right):\dfrac{1}{2}-\dfrac{1}{4}=\dfrac{2}{3}\)
\(5\left(2x-3\right):\dfrac{1}{2}=\dfrac{11}{12}\)
\(5\left(2x-3\right)=\dfrac{11}{24}\)
\(2x-3=\dfrac{11}{120}\)
\(2x=\dfrac{371}{120}\)
\(x=\dfrac{371}{240}\)
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\(b,x-\dfrac{3}{5}=3x+\dfrac{2}{6}\)
\(x-3x=\dfrac{3}{5}+\dfrac{2}{6}\)
\(-2x=\dfrac{14}{15}\)
\(x=\dfrac{14}{15}:\left(-2\right)\)
\(x=\dfrac{-7}{15}\)