It seems that the expression is - 7x + 3y - 2 + 6x -1 - y^2
like terms:
-7x + 6x = - x
3y stands alone
-2 - 1 = -3
- y^2 stands alone
Answer: - x + 3y - 3 - y^2
[note: if the last term is not y^2 but 2y, then you have to combine +3y - 2y = y and the answer would be - x + y - 3]