Answer: x=9 is an extraneous solution
Step-by-step explanation:
Given
Function is [tex]f(x)=\sqrt{x-5}[/tex]
for function to exist
[tex]\Rightarrow x-5\geq 0\\\Rightarrow x\geq 5[/tex]
Therefore, 9 satisfies the above equation. It is it's extraneous solution.