Use the substitution \(\sqrt{x} = y\) (where \(y \geq 0\)) to find the real root of the equation \[x + 3\sqrt{x} − \tfrac{1}{2} = 0.\]

Find all real roots of the following equations:

\(x + 10\sqrt{x + 2} − 22 = 0\);

\(x^2 − 4x + \sqrt{2x^2−8x−3} − 9 = 0\).