$$\frac{ 2z+6 }{ 4x+2 } = \frac{ 4x+12 }{ 2 }$$
$z=4x^{2}+14x+3$
$x\neq -\frac{1}{2}$
$\left\{\begin{matrix}x=\frac{\sqrt{4z+37}-7}{4}\text{, }&z\neq -3\text{ and }z\geq -\frac{37}{4}\\x=\frac{-\sqrt{4z+37}-7}{4}\text{, }&z\geq -\frac{37}{4}\end{matrix}\right.$
