c, \(\dfrac{3}{5}-x=\dfrac{5}{6}+\dfrac{13}{20}=\dfrac{100+78}{120}=\dfrac{178}{120}=\dfrac{89}{60}\Leftrightarrow x=-\dfrac{53}{60}\)
d, \(\left(x-\dfrac{1}{4}\right)^2=\dfrac{25}{64}\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{4}=\dfrac{5}{8}\\x-\dfrac{1}{4}=-\dfrac{5}{8}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{7}{8}\\x=-\dfrac{3}{8}\end{matrix}\right.\)