How to borrow if you can't subtract from the lowest number on top

Go to the number next to the one you cannot subtract from, take one away, and add a one in front of the number you cannot subtract from. e.g. 
27      1(1)7             the answer would be 9
-8             -8

for your problem the answer would be 1109

           8  1
      7898
   -  6789
     
       1109    is your answer
  And to borrow you just subtract from the number before it and add 10 

As you know john locke said he wanted life liberty and the pursuit of happiness so thomas jefferson was inspired about what john locke said so thomas jefferson wrote the declaration of independence for people to be free for people to be happy

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