Adding and Subtracting Integers

Integers include zero, counting numbers, and the negative of the counting numbers.

{... ,, ...}

-  Add a positive integer by moving to the right on the number line. (you will get a bigger number)
-  Add a negative integer by moving to the left on the number line. (you will get a smaller number)
-  Subtract an integer by adding its opposite.


Examples:
Example 1.  Solve.
Solution: Keep the first number and convert the sign of the second number to its opposite. (change subtraction into addition. Then:  

Example 2.  Solve.
Solution: First, subtract the numbers in brackets, .
Then:   → change addition into subtraction:  

Example 3.  Solve.
Solution: First, subtract the numbers in brackets,
Then:   →  

Example 4.  Solve.
Solution: First, subtract the numbers in brackets,
Then:   → change addition into subtraction: