Have you tried multiplying 5(3)+2(2)+1?
15 + 4 + 1 = 20 ? 
Im sorry I'm not real good with math. 
 
        
                    
             
        
        
        
She would need to work 24 hours because the first 20hrs x $4 is $80 $104-$80 = 24 
24\6= 4 20 plus 4 is 24
        
             
        
        
        
Answer: The answer is 1 =n and my work is in the bottom and hope this help :)
Step-by-step explanation:
5n+7=7(n+l)-2n distributive property
5n+7=7n+7-2n  Combines Like Term
5n+7= 12n  subtract 5n to both side 
-5n      -5n 
     7 = 7n   divide 7n to both side 
      7    7
         1=n