1. Integers

2. Introducing integers
A positive or negative whole number, including zero, is called an integer.
It is 3 less than 0.
The number line goes on forever in both directions and is indicated by arrows.
An integer is always bigger than any integer on its left.
Whole numbers greater than zero are positive integers and these numbers are to the right of zero.
Whole numbers smaller than zero are negative integers and are to the left of zero.
The integer zero is neither positive nor negative
Or in words,
‘zero minus three equals negative three’

3. Integers on a number line
Positive and negative integers can be shown on a number line. –8 –3
Negative integers
Positive integers
We can use the number line to compare integers.
Discuss what we mean when we use the terms ‘greater than’ and ‘less than’ with negative numbers. We say that –3 is ‘greater than’ –8 because it is further along the line in the positive direction.
For example,
–3 ‘is greater than’ –8

4. Ordering integers –9, –6, –2, 2, 5, and 8
Write the integers –2, 8, 2, –6, –9 and 5 in order from smallest to largest.
Look at the position of the integers on the number line: –9 –6 –2 2 5 8
Together, order the numbers on the number line.
So, the integers in order are:
–9, –6, –2, 2, 5, and 8

5. List 4 integers smaller than 2
List all the integers between -4 and 1

6. Why do we need integers?

7. Budgets and Money Application
The positive numbers represent income while the negative numbers represent debt.

8. Money Solve the following problem using integers.
Jenny has R2. She earns R5, spends R10, earns R4, then spends R3.
How many Rands does she have or owe?

9. Worksheet 1
Homework