1. Rules for Adding & Subtracting Integers

2. Adding & Subtracting Integers
Any SUBTRACTION problem can be expressed as an ADDITION problem by…
“ADDING THE OPPOSITE”
16 – becomes?
16 + (-10)
-26 – becomes?
-26 + (-13)
15 – (-22) becomes?
15 + (+22)
-42 – (-14) becomes?
-42 + (+14)

3. METHOD 1 – SAME SIGN When adding integers with the SAME SIGN
(i.e. both positive or both negative)
Example:
(-234)
Make both integers positive (absolute value!)
ADD the numbers
If the original integers were POSITIVE, the final answer is POSITIVE
If the original integers were NEGATIVE, the final answer is NEGATIVE
356
Nope!
Yup!
Answer: -356

4. METHOD 2 – DIFFERENT SIGN
When adding integers with
DIFFERENT SIGNS
Example:
122 + (-234)
Make both integers positive (absolute value!)
SUBTRACT the smaller from the larger
If the larger integer was POSITIVE, the final answer is POSITIVE
If the larger integer was NEGATIVE, the final answer is NEGATIVE
234 – 122
112
Nope!
Yup!
Answer: -112