8+3=11 11-5=6
9+6=15 15-7=8
8+5=13
The only think you have to do is add and tracted and you'll get the answer that's all you have to do it's easy if you didn't get it I give the answer to you if you don't know which one is the answer the correct answer is 13 I don't know maybe some people has different ways I did it this way because it was more easier