\( 4 + 2x\left( {2x + 4} \right) = - x\\ \Leftrightarrow 4 + 4{x^2} + 4 = - x\\ \Leftrightarrow 4{x^2} + x = 0\\ \Leftrightarrow x\left( {4x + 1} \right) = 0\\ \Leftrightarrow \left[ \begin{array}{l} x = 0\\ 4x + 1 = 0 \end{array} \right. \Leftrightarrow \left[ \begin{array}{l} x = 0\\ x = - \dfrac{1}{4} \end{array} \right. \)