Answer:
=18
Step-by-step explanation:
No entiendo....................
The difference of the expression
is 
<h3>How to determine the difference?</h3>
The expression is given as:

Factor the denominators of the expressions:

Apply the difference of two squares to x² - 9

Take LCM

Hence, the difference of the expression
is 
Read more about expressions at:
brainly.com/question/723406
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