For the Pair of Functions, Determine the Domain of F $$f ( x ) = \frac { 2 x } { x - 1 } , g ( x ) = \frac { 4 } { x + 9 }$$

Multiple Choice

For the pair of functions, determine the domain of f + g.
- $$f ( x ) = \frac { 2 x } { x - 1 } , g ( x ) = \frac { 4 } { x + 9 }$$

A) $( \infty , \infty )$
B) $( \infty , - 9 )$ or $( 1 , \infty )$
C) $( \infty , - 1 )$ or $( - 1,9 )$ or $( 9 , \infty )$
D) $( - \infty , - 9 )$ or $( - 9,1 )$ or $( 1 , \infty )$