Some books say Log is the Ln and the other it is base 10. I am not sure what your book states so I will discuss both which are identical in manner.
This is what we obtain through simplification. Here is when we should observe the domain as well. If x = 3, then we would have the log(0) = DNE so 3 is out and if x = 0, we would be dividing by 0 so 0 is out.
Now to isolate the terms inside the log, we raise log base 10 to 10th power and ln to the e.
Now you try the rest.