Final answer:
To find the LCD of the given fractions, factor the denominators and determine the common factors. The LCD is the product of all the unique factors.
Step-by-step explanation:
To find the LCD (Least Common Denominator) of the fractions (5)/(x-3) and (4)/(x²-9), we need to factor the denominators and determine the common factors.
The denominator x-3 can be factored as (x-3) and the denominator x²-9 can be factored as (x-3)(x+3).
The LCD is the product of all the unique factors, so the LCD in this case is (x-3)(x+3).