Given the equation $$x^2 - 7nx + 12n^2 = 0$$ and $$n=3$$, substitute $$n=3$$ into the equation:
$$x^2 - 7(3)x + 12(3)^2 = 0$$
$$x^2 - 21x + 12(9) = 0$$
$$x^2 - 21x + 108 = 0$$
Using Vieta's formulas, we need two numbers that multiply to 108 and add up to 21. These numbers are 9 and 12.
Therefore, the roots are $$x_1 = 9$$ and $$x_2 = 12$$.