Work Shown:
Let x be the additive inverse of 9
This means it adds to 9 to get 0
x+9 = 0 which solves to x = -9 after subtracting 9 from both sides.
So -9+9 = 0 and 9+(-9) = 0.
Answer:
-9.
Step-by-step explanation:
Because 9 + (-9) = 0.
