A general rule when attempting to simplify compound fractions is as follows:
Identify all the denominators of fractions in the numerator of the major fraction.
Identify all the denominators of fractions in the denominator of the major fraction.
Determine the least commonmultiple of these denominators.
Multiply both numerator and denominator of the major fraction by this lcm.
In other words, multiply numerator and denominator of the major fraction by the least common denominator of the fractions appearing within the major fraction.
In your case, multiply both numerator and denominator of the original compound fraction by x-5.
Please recognize that this is possible because you are multiplying the original compound fraction by 1, which is in the form of \(\displaystyle \frac{x-5}{x-5}\).