a: \(\frac85x-\frac43x=\left(-\frac{5}{16}\right)\cdot1\frac25\)
=>\(x\left(\frac85-\frac43\right)=-\frac{5}{16}\cdot\frac75=-\frac{7}{16}\)
=>\(x\left(\frac{24}{15}-\frac{20}{15}\right)=-\frac{7}{16}\)
=>\(x\cdot\frac{4}{15}=-\frac{7}{16}\)
=>\(x=-\frac{7}{16}:\frac{4}{15}=-\frac{7}{16}\cdot\frac{15}{4}=\frac{-105}{64}\)
b: \(\frac23-\left|4x+\frac12\right|=\frac13\)
=>\(\left|4x+\frac12\right|=\frac23-\frac13=\frac13\)
=>\(\left[\begin{array}{l}4x+\frac12=\frac13\\ 4x+\frac12=-\frac13\end{array}\right.\Rightarrow\left[\begin{array}{l}4x=\frac13-\frac12=-\frac16\\ 4x=-\frac13-\frac12=-\frac56\end{array}\right.\Rightarrow\left[\begin{array}{l}x=-\frac16:4=-\frac{1}{24}\\ x=-\frac56:4=-\frac{5}{24}\end{array}\right.\)
