Answer :

naǫ
[tex]x^2-14x+48=0 \\ \\ a=1 \\ b=-14 \\ c=48 \\ b^2-4ac=(-14)^2-4 \times 1 \times 48=196+192=4 \\ \\ x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}=\frac{-(-14) \pm \sqrt{4}}{2 \times 1}=\frac{14 \pm 2}{2}=\frac{2(7 \pm 1)}{2}=7 \pm 1 \\ x=7-1 \ \lor \ x=7+1 \\ x=6 \ \lor \ x=8 \\ \boxed{x=6 \hbox{ or } x=8}[/tex]