Answer: 5
Explanation:
Hi, to answer this question we have to know that 
We have to subtract when two different signs appear next to each other (-+ or +-) 
We have to add when two of the same signs appear next to each other (++ or --) 
So: 
5+(-11)-(-11) 
5-11+11 
5 
Feel free to ask for more if needed or if you did not understand something.