## Algebra: A Combined Approach (4th Edition)

Two numbers that are the same distance from 0 but lie on opposite sides of 0 are called opposites of each other. Furthermore, we know that the sum of a number $a$ and its opposite $-a$ is 0. Therefore, the opposite of 0 is 0, because $0+0=0$. In other words, the opposite of 0 is 0 itself.