Well, one thing they ahve in common is that they are both adding or subtracting the same numbers and of course, they are both expressions. 
They are different because one expression is subtract both numbers while one expression is adding both numbers.
8 - 15 = -7
8 + 15 = 23
Best of Luck!
 
        
             
        
        
        
Answer:
quit school its trash
Step-by-step explanation:
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Given parameters: 
         1.         
  
  
           ; find the LCM = 8
; find the LCM = 8
   
              =     
        
              =      
 
     
        2.    
  
             Make the fraction decimal; 
               = -2.4
   = -2.4
             So; 
                         -2.4 + 15.3  = 12.9   
 
        
             
        
        
        
Answer:
The original nimber is 67.
Step-by-step explanation:
Let the two digits be x and y.
According to the question.
The sum of two digits of a two digit number is
x + y = 13
or, x = 13 - y
And, a two digit number can be written as
x × 10 + y
when the digits are reversed, the number can be written as 
y × 10 + x
 the original number increases by 9. i.e.
y x 10 + x = x × 10 + y + 9
Replacing value of x by 13 - y,
y × 10 + 13 - y = 10(13 - y) + y + 9
10y + 13 - y = 130 - 10y + y + 9
9y + 13 = 139 - 9y
18y = 139 - 13
18y = 126
y = 126/18
y = 7
So, x = 13 - y 
 = 13 - 7
 = 6
The original number is x × 10 + y = 6 x 10 + 7 = 67.
 
        
             
        
        
        
0.20833 these how you simplify it!