[tex]The\ distance\ between\ A(x_A;\ y_A)\ and\ B(x_B;\ y_B):\\\\d=\sqrt{(x_B-x_A)^2+(y_B-y_A)^2}\\\\------------------------------\\\\A(6;\ 5);\ B(4;\ 3)\\\\subtitute\\\\d=\sqrt{(4-6)^2+(3-5)^2}=\sqrt{(-2)^2+(-2)^2}=\sqrt{4+4}\\\\=\sqrt{4\cdot2}=\sqrt4\cdot\sqrt2=\boxed{2\sqrt2}[/tex]
