Opposite Numbers (Противоположные числа)
Opposite numbers are like mirror images on a number line — they are the same distance from zero but on opposite sides!
📖 What Are Opposite Numbers?
Definition: Two numbers are opposite if they are the same distance from zero on the number line, but on different sides.
- +5 and −5 are opposites
- +7 and −7 are opposites
- +100 and −100 are opposites
They differ only by their sign!
✏️ Mathematical Notation
The opposite of a number a is written as −a
| Number | Opposite | Written as |
|---|---|---|
| +5 | −5 | −(+5) = −5 |
| −3 | +3 | −(−3) = +3 |
| +8 | −8 | −(+8) = −8 |
Tip: Use parentheses for clarity: −(−8) = +8
📊 Opposite Numbers on the Number Line
Opposite numbers are symmetric about zero — they are mirror images of each other!
Interactive visualization — available in the full lesson
Blue point (+5): 5 units to the RIGHT of zero
Red point (−5): 5 units to the LEFT of zero