# Opposite number

## number that, when added to the original number, yields zero / From Wikipedia, the free encyclopedia

In mathematics, the **opposite** or **inverse** of a number $k$ is an additive or a subtractive number $n$ which, when added to $k$, results in 0. The opposite of $a$ is $-a$.^{[1]}^{[2]} For example, −7 is the opposite of 7, because $7+-7=0$.