Question

$raiz de 2+x=9$

Answer 1

$\sqrt{2+x} =9\to \\ \\ (\sqrt{2+x})^2 =9^2\to \\ \\ 2+x=81\to \\\\ x=81-2\to \\\\ \boxed{\boxed{x=79}}\\\\\\\\Verificando:\\\\ \sqrt{2+79} =9\to \\\\ \sqrt{81} =9\to \\\\ \boxed{9=9}$