7th Grade · The Number System
Opposites
7.NS.A.1a
Definition
Two numbers the same distance from zero on a number line but on opposite sides. The opposite of n is −n, and the sum of opposites is always 0.
Examples
- The opposite of 5 is −5; the opposite of −8 is 8.
- 5 + (−5) = 0 — opposites sum to zero.
Key rule
Opposites are also called additive inverses; their sum is zero.
Memory hook
Opposites cancel to zero.