Solve the Equation by the Method of Your Choice $$x ^ { 2 } + 12 x + 15 = 0$$

Multiple Choice

Solve the equation by the method of your choice.
- $$x ^ { 2 } + 12 x + 15 = 0$$

A) $\{ 6 - \sqrt { 15 } , 6 + \sqrt { 15 } \}$
B) $\{ - 12 + \sqrt { 15 } \}$
C) $\{ 6 + \sqrt { 21 } \}$
D) $\{ - 6 - \sqrt { 21 } , - 6 + \sqrt { 21 } \}$