Find the Coordinates of the Vertex of the Quadratic Function $$f ( x ) = x ^ { 2 } - 6 x - 9$$

Find the coordinates of the vertex of the quadratic function.
- $$f ( x ) = x ^ { 2 } - 6 x - 9$$

A) $( 3 , - 18 )$
B) $( - 3,18 )$
C) $( 3 , - 36 )$
D) $( - 6,63 )$