X/2 + x/2 = 2x / 2 or just x. So x = 8/12 which can be simplified by their greatest common factor of 4. Divide both top and bottom by 4. This gives you x = 2/3. 
Your answer for that equation is x = 2/3
Not sure what you mean by "decompose" though. 
        
             
        
        
        
8x + c = 5d
First move c by subtraction it.
8x = 5d - C
Then move the 8 by dividing it.
x = 5/8d - C
        
             
        
        
        
Answer:
D) 72 is correct because 8 times 9 is 72! Hope this helped. :)
 
        
             
        
        
        
Answer:
Division Property of Equality.
Step-by-step explanation:
In this case, you will use the Division Property of Equality to solve. Isolate the variable, n, by dividing 5 from both sides: 
(5n)/5 = (50)/5
n = 50/5
n = 10
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