NUM003 · Numbers & number systems · Classes 6–8
Integers
Integers are the whole numbers and their negatives: …, −3, −2, −1, 0, 1, 2, 3, … On a number line, moving right adds and moving left subtracts.
−3 … +5Integers
📐 Formula
a − b = a + (−b); distance between a and b = |a − b|
✏️ Worked example
a = −3, b = 5: −3 + 5 = 2, −3 − 5 = −8, and the distance between them is |−3 − 5| = 8.
🌍 Where it is used
Temperatures below zero, floors below ground, bank balances and heights below sea level.
❓ Quick check
What is −7 + 4?
🏋️ Practice
EasyWhich is greater, −2 or −6?
Answer: −2
MediumThe temperature is −4 °C and rises by 9 °C. What is it now?
Answer: 5 °C
Challenge(−6) − (−10) = ?
Answer: 4