Solving $2\left(\sqrt{2s-16}-\sqrt{s}\right)-8=0$ I am trying to solve the equation 
$$2\left(\sqrt{2s-16}-\sqrt{s}\right)-8=0$$ 
Using regular method I found two roots of this namely $32(2+\sqrt{3})$ and $32(2-\sqrt{3})$. But when I tried to confirm them only $32(2+\sqrt{3})$ worked as a root whereas $32(2-\sqrt{3})$ gave me negative value. 
Can someone help with this?

Whenever you square an equation you get additional roots. For example $x=1$ has a unique solution but $x^{2}=1^{2}$ has two solutions $x=1$ and $x=-1$. Your 'regular method' involves squaring so you got an extra root. After getting the two values for $s$ you have to go back to the given equation and keep only the one that really satisfies that equation. 
