find the lcd (x+18)(x-18)

Question

Please find the lcd

Answer 1

Those aren't fractions, so there's nothing to find for the LCD (least common denominator).

Or, you could say "what is the LCD of (x+18)/1 and (x-18)/1 ?"  Then the LCD would be 1.

If you mean "what is the LCM (least common multiple) of x+18 and x-18 ?" then it's (x+18)*(x-18) = x^2 - 324