Answer:
<u>2</u><u>7</u><u> </u><u>+</u><u> </u><u>7</u><u>m</u>
Step-by-step explanation:

open the bracket:

 
        
             
        
        
        
The sum means addition
v + 3
        
             
        
        
        
If Dylan owes half as much as he used to that would imply that the 28$ would be divided by two which would be 14$, which means that half of what he owed 28$ would now be 14$.