 Integers are whole numbers and their opposites and zero. Here you can learn how to add and subtract integers.

## Step by step guide to add and subtract integers

• Integers include: zero, counting numbers, and the negative of the counting numbers. $$\{… , – \ 3, – \ 2, – \ 1, 0, 1, 2, 3 , …\}$$
• Add a positive integer by moving to the right on the number line.
• Add a negative integer by moving to the left on the number line.
• Subtract an integer by adding its opposite.

### Example 1:

Solve. $$(- \ 2) \ – \ (- \ 6)=$$

Solution:

Keep the first number, and convert the sign of the second number to it’s opposite. (change subtraction into addition. Then: $$(- \ 2) \ \color{blue}{+} \ 6=4$$

### Example 2:

Solve. $$8 \ + \ (12 \ – \ 20)=$$

Solution:

First subtract the numbers in brackets, $$12 \ – \ 20= \ – \ 8$$
Then: $$8 \ + \ (- \ 8)= \ →$$ change addition into subtraction: $$8 \ \color{blue}{-} \ 8=0$$

### Example 3:

Solve. $$(-8)-(-5)=$$

Solution:

Keep the first number and convert the sign of the second number to it’s opposite. (change subtraction into addition. Then: $$(-8)+5= \ -3$$

### Example 4:

Solve. $$10+(4-8)=$$

Solution:

First subtract the numbers in brackets, $$4-8= \ -4$$
Then: $$10+(-4)= →$$ change addition into subtraction: $$10-4=6$$

## Exercises

### Find the sum and the difference.

• $$\color{blue}{(– 12) + (– 4)}$$
• $$\color{blue}{5 + (– 24)}$$
• $$\color{blue}{4 + (– 30) + (45 – 34)}$$
• $$\color{blue}{( – 14) – (– 9) – (18)}$$
• $$\color{blue}{( – 9) – (– 25)}$$
• $$\color{blue}{(55) – (– 5) + (– 4)}$$

• $$\color{blue}{-16}$$
• $$\color{blue}{-19}$$
• $$\color{blue}{-15}$$
• $$\color{blue}{-23}$$
• $$\color{blue}{16}$$
• $$\color{blue}{56}$$ 