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.