Find the Vertex of the Graph of the Quadratic Function $f ( x ) = x ^ { 2 } + 6 x - 7$

Multiple Choice

Find the vertex of the graph of the quadratic function.
- $f ( x ) = x ^ { 2 } + 6 x - 7$

A) $( 6,65 )$
B) $( - 3 , - 34 )$
C) $( 3,20 )$
D) $( - 3 , - 16 )$