c: \(-\dfrac{4}{5}x-\left(0,25-x\right)=-\dfrac{13}{3}\)
=>\(-\dfrac{4}{5}x-0,25+x=-\dfrac{13}{3}\)
=>\(\dfrac{1}{5}x-\dfrac{1}{4}=-\dfrac{13}{3}\)
=>\(\dfrac{1}{5}x=-\dfrac{13}{3}+\dfrac{1}{4}=-\dfrac{52}{12}+\dfrac{3}{12}=-\dfrac{49}{12}\)
=>\(x=-\dfrac{49}{12}\cdot5=-\dfrac{245}{12}\)
d: \(\left(\dfrac{12}{7}:x-0,5\right)\left(\dfrac{2}{5}x-1\dfrac{1}{2}\right)=0\)
=>\(\left[{}\begin{matrix}\dfrac{12}{7}:x-0,5=0\\\dfrac{2}{5}x-\dfrac{3}{2}=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}\dfrac{12}{7}:x=\dfrac{1}{2}\\\dfrac{2}{5}x=\dfrac{3}{2}\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}x=\dfrac{12}{7}:\dfrac{1}{2}=\dfrac{24}{7}\\x=\dfrac{3}{2}:\dfrac{2}{5}=\dfrac{3}{2}\cdot\dfrac{5}{2}=\dfrac{15}{4}\end{matrix}\right.\)
