Find the Vertex of the Graph of the Function $f ( x ) = 3 x ^ { 2 } + 18 x + 23$

Multiple Choice

Find the vertex of the graph of the function.
- $f ( x ) = 3 x ^ { 2 } + 18 x + 23$

A) $( - 3 , - 4 )$
B) $( - 4 , - 3 )$
C) $( 5,4 )$
D) $( 4,5 )$