|-2x|=3x+4
\(\Leftrightarrow\left\{{}\begin{matrix}x>=-\dfrac{4}{3}\\\left(3x+4-2x\right)\left(3x+4+2x\right)=0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x>=-\dfrac{5}{3}\\\left(x+4\right)\left(5x+4\right)=0\end{matrix}\right.\)
hay x=-4/5