$$x=y^{2}+z; Z=y^{3}\times2; Z=3; x=$$
$x=a$
$y = \frac{\sqrt[3]{3} \cdot 2 ^ {\frac{2}{3}}}{2} = 1.1447142425533317$
$z = -\frac{\sqrt[3]{2} \cdot 3 ^ {\frac{2}{3}}}{2} = -1.3103706971044484$
$Z=3$
