answer
1 or 3
explaination
[tex] {x}^{2} - 4x + 3 = 0 \\ using \: factorization \: method \\ ( {x}^{2} - 3)( - x + 3) = 0 \\ x(x - 3) - 1(x - 3) \\ x - 1 = 0 \: orx - 3 = 0 \\ x = 1 \: or \: 3[/tex]