\(a.\)
\(x+\left(-17\right)=-24\)
\(\Leftrightarrow x=-24+17=-7\)
\(b.\)
\(\dfrac{3}{7}x-\dfrac{1}{2}=\dfrac{3}{14}\)
\(\Leftrightarrow\dfrac{3}{7}x=\dfrac{3}{14}-\dfrac{1}{2}=\dfrac{3}{14}-\dfrac{7}{14}=-\dfrac{2}{7}\)
\(\Leftrightarrow x=-\dfrac{2}{7}:\dfrac{3}{7}=-\dfrac{2}{3}\)