Answer:
(x-4) (x-1)(x+1)
Step-by-step explanation:
denominator 1 x^2 -5x+4
factor
(x-4) (x-1)
denominator 2 x^2 -16
factor
(x-4) (x+4)
to find the LCD you have to find the LCM of the denominator
LCM Multiply each factor the greatest number of times it occurs in any of the numbers.
LCD: (x-4) (x-1)(x+1)
