Yes, the table represents a function.
None of the independent (x) values are repeated and each one has a corresponding (y) value.
If you had a repeated (x) value in the table, it would not represent a function.
Hello! Let's work this problem from left to right to make things a bit easier ;)
6.5+(-2) is the same as 6.5-2, since adding a negative is the same as subtracting a positive. 6.5-2=4.5
Now, we have to add 10.5 to 4.5, which gives us the grand total of 15. I hope this helped! Let me know if you need anything else!