I need help please thank you

Answer:
A
Step-by-step explanation:
in the question given, the goal is to rationalize the denominator, or in other words get rid of any square roots.
recall this formula :
(a-b)(a+b) = a^2 - b^2
in this case, to rationalize the denominator of 3 - [tex]\sqrt{6x}[/tex] , we will multiply it and the numerator by its conjugate. the conjugate of 3 -
after multiplying the denominator by its conjugate, we get:
(3 - [tex]\sqrt{6x}[/tex]) (3 +
at this point there is no need to solve the numerator as there is only one answer with this denominator.
hope this helps :)