5) \(\left|4+2x\right|=-4x\)
\(\Leftrightarrow\left\{{}\begin{matrix}-4x\ge0\\4+2x=-4x\cup4+2x=4x\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\le0\\6x=-4\cup2x=4\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\le0\\x=-\dfrac{2}{3}\left(tm\right)\cup x=2\left(ktm\right)\end{matrix}\right.\)
\(\Leftrightarrow x=-\dfrac{2}{3}\)
6) \(\left|3x-1\right|+2=x\)
\(\Leftrightarrow\left|3x-1\right|=x-2\)
\(\Leftrightarrow\left\{{}\begin{matrix}x-2\ge0\\3x-1=x-2\cup3x-1=2-x\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\ge2\\2x=-1\cup4x=3\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\ge2\\x=-\dfrac{1}{2}\left(ktm\right)\cup x=\dfrac{3}{4}\left(ktm\right)\end{matrix}\right.\)
\(\Leftrightarrow x\in\varnothing\)
