`sqrt{3x^2 - 9x + 1} = x - 2` `(x >= 2)`
`<=> 3x^2 - 9x + 1 = (x - 2)^2`
`<=> 3x^2 - 9x + 1 = x^2 - 4x + 4`
`<=> 2x^2 - 5x - 3 = 0`
`<=> (x - 3)(2x + 1) = 0`
`<=>` \(\left[ \begin{array}{l}x - 3 = 0\\2x + 1 = 0\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}x = 3\\x = -\dfrac{1}{2}\end{array} \right.\)
`=> x = 3`