\(\Leftrightarrow-4x^2-6x=0\)
\(\Rightarrow2x\left(-2x-3\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\-2x-3=0\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=0\\-2x=3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\frac{-3}{2}\end{matrix}\right.\)
Vậy: \(x\in\left\{0;\frac{-3}{2}\right\}\)