Square both sides

Simplify



Subtract 5 from both sides to get 0 on the right

Rearrange terms in descending order:

Use the quadratic formula:
 
 
 
 
 
 
Factor out 10 in the numerator:
 
Divide top and bottom by 10
 

Using the +:

 
 
 
 

Checking in the original equation:







That doesn't check so we must discard  

Using the -:

 
 
 
 

Checking in the original equation:







That checks, so the only solution is  

Note, you must always check equations with square roots
because oftentimes there are extraneous "answers".

Edwin

 =    --->   =    --->  x = ,  or,  which is the same,  x = .

It is yours very final answer.  One line solution.