<=> x- 7√x+12=0
<=> (√x)2 -4√x-3√x +12=0
<=> √x(√x-4)-3(√x-4)=0
<=> (√x-3)(√x-4)=0
=> x=9 hoặc x=16
Ta có: \(x+\sqrt{x}-4=8\sqrt{x}-16\)
\(\Leftrightarrow x-7\sqrt{x}+12=0\)
\(\Leftrightarrow\left(\sqrt{x}-3\right)\left(\sqrt{x}-4\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=9\\x=16\end{matrix}\right.\)