Read this lesson on completing the square by prince_abubu, if you do not know how to complete the square. Let's convert   to standard form by dividing both sides by 1:  
We have:  . 
What we want to do now is to change this equation to a complete square  . How can we find out values of somenumber and othernumber that would make it work? 
Look at  :  . Since the coefficient in our equation   that goes in front of x is -0.66, we know that -0.66=2*somenumber, or  . So, we know that our equation can be rewritten as  , and we do not yet know the other number. 
We are almost there. Finding the other number is simply a matter of not making too many mistakes. We need to find 'other number' such that    is equivalent to our original equation  . 
   
    
  The highlighted red part must be equal to 0 (highlighted green part). 
   
   , or  . 
So, the equation converts to  , or  . 
   
    Our equation converted to a square  , equated to a number (0.1089). 
   
    Since the right part 0.1089 is greater than zero, there are two solutions: 
   
       
    , or 
   
       
       
       
     
       
Answer: x=0.66, 0.
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