Answer:
it is 6
Step-by-step explanation:
2 and 6 are the denominators and the least common denominator is the number in which 2 & 6 can go in without leaving a remender and 6 is that number 
 
        
                    
             
        
        
        
The answer is:  [A]:  " 20a − 5b − 9 " .
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Explanation:
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  (12a <span>+ 7b) + (−6a − 9) + (14a − 12b) =
 
   12a </span><span>+ 7b  +  1(−6a − 9) + 1(14a − 12b) =
</span>    
   12a + 7b + (1*-6a) + (1*-9) + (1*14a) + (1* -12b) =
      
    12a + 7b − 6a − 9 + 14a − 12b =  ?
Combine the "like terms:
12a − 6a  + 14a = 20a ; 
7b − 12b =  - 5b ;
and then we have "-9" ;
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So, write as:   " 20a − 5b − 9 " ;  which is:  Answer choice:  [A].
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Answer:
2+2=4
Step-by-step explanation: