Răspuns: B
Explicație pas cu pas:
[tex]x^{2} -4x+3=0\\a=1\\b=-4\\c=3\\\\delta=b^{2} -4ac\\delta=16-12\\delta=4x_{1} =\frac{-b+ \sqrt{delta} }{2a}\\x_{1} =\frac{4+2}{2} \\x_{1}=3\\x_{2}=\frac{-b-\sqrt{delta} }{2a} \\x_{2}=\frac{4-2}{2} \\x_{2}=1\\x={1;3}[/tex]