Hello dear,
Refer to this solution

We can write,

Log(x+3)-log(x-3) as log(x+3)/(x-3)
And 1 as log 0.

We get,
Log(x+3)/(x-3) = log0

Which gives,   (x+3)/(x-3) = 0
That is,  (x+3) = 0

Hence,
X= -3.

Thank you.