Answer:
A)
Step-by-step explanation:
We know that the expression (x^2 - a^2) can be written as (x-a)(x+a). So an expression of this type: (x^2 - a^2) wouldn't be completely factored because it could be factorized even more.
So we know that 36 = 6^2, 49= 7^2 and 81 = 9^2. So if we choose any of these options (Option B, C and D) it wouldn't be completely factored.
The correct is the option A, given that if a=12, it wouldn't be a perfect square, so it would be completely factored. 
 
        
                    
             
        
        
        
3+2 = 5
80/5 =16
16 x 3 = 48
16 x 2 = 32
Answer= 48:32
I think this is right
        
                    
             
        
        
        
Answer:
It's 1/2
Step-by-step explanation:
 
        
                    
             
        
        
        
9xa is the common factor.
You can complete the statement by dividing the two terms of the expression of the left side by 9xa, and you will get: 
36x^3a + 45xa^2 = 9xa ( 4x^2 + 5a)
        
             
        
        
        
36, because 6^4 /6^2 is 6^2 and 6*6 (6^2) is 36