Find the Vertex of the Graph of the Quadratic Function $f ( x ) = - 6 x ^ { 2 } + 12 x + 9$

Multiple Choice

Find the vertex of the graph of the quadratic function.
- $f ( x ) = - 6 x ^ { 2 } + 12 x + 9$

A) $( 1,15 )$
B) $( - 2 , - 39 )$
C) $( 2 , - 3 )$
D) $( - 1 , - 9 )$