(x + 9)^2 - 6^2 = 0;
(x + 9 - 6)(x + 9 + 6) = 0;
(x + 3)(x + 15) = 0;
1) x + 3 = 0;
x = -3;
2) x + 15 = 0;
x = -15.
(x + 9)^2 - 6^2 = 0;
(x + 9 - 6)(x + 9 + 6) = 0;
(x + 3)(x + 15) = 0;
1) x + 3 = 0;
x = -3;
2) x + 15 = 0;
x = -15.