15 POINTS FOR THE BRIANLEIST! PLEASE SOLVE!!

Answer:
y = -y
Step-by-step explanation
So since we know that the answer of this question turns out to be a positive, and 5 is a negative number, that means y is negative. Heres my reason why:
( write this down on your essay)
Since a negative number and another negative number added becomes a positive, y would be a negative number.
Therefore, It is true that y is a negative number