Решите пожалуйста приклад

$\frac{x^{4}-x^{2}-12}{x+2} =0 \\ \left \{ {{x^{4}-x^{2}-12=0} \atop {x+2 \neq 0}} \right. \\ \left \{ {{x^{4}-x^{2}-12=0} \atop {x \neq -2}} \right. \\ x^{4}-x^{2}-12=0 \\ x^{2} =z \\ z^{2}-z-12=0 \\ z_{1}+z_{2}=1 \\ z_{1}z_{2}=-12 \\ z_{1}=4 \\ z_{2}=-3 \\$
$\\ x^{2} =4 \\ x^{2} \neq -3 \\ \left \{ {{x^{2} =4} \atop {x \neq -2}} \right. \\ \left \{ {{x=2} \atop {x \neq -2}} \right. \\$
Ответ: x=2