For the Given Functions F and G, Find the Requested $f ( x ) = 2 x + 1 ; g ( x ) = 3 x + 9 \quad$

For the given functions f and g, find the requested function.
- $f ( x ) = 2 x + 1 ; g ( x ) = 3 x + 9 \quad$ Find $( f \cdot g ) ( x )$

A) $( f \cdot g ) ( x ) = 6 x ^ { 2 } + 9$
B) $( f \cdot g ) ( x ) = 5 x ^ { 2 } + 21 x + 10$
C) $( f \cdot g ) ( x ) = 6 x ^ { 2 } + 12 x + 9$
D) $( f \cdot g ) ( x ) = 6 x ^ { 2 } + 21 x + 9$