Answer:
x = 5 is not in the domain
Step-by-step explanation:
Given
f(x) = [tex]\frac{4}{x-5}[/tex]
The denominator cannot equal zero as this would make f(x) undefined.
Equating the denominator to zero and solving gives the value that x cannot be, that is
x - 5 = 0 ⇒ x = 5 ← excluded value
Thus the domain is all real except x ≠ 5