1. Using Rules to Subtract Integers

2. To subtract an integer… ADD it’s OPPOSITE!

3. Let’s look at 2 – 5;
Rewrite 2 – 5 to 2 + (–5).
Now use addition rules.

4. Different Signs
Find the difference (subtract) the two absolute values. The sum (answer) keeps the sign of the integer with the greatest absolute value.

5. 2 + (–5)
|–5| – |2| = 5 – 2 =3
More negatives, right?
= –3

6. Here’s another one.
2 – (–5)
Rewrite 2 – (–5) to 2 + 5
2 + 5 = 7

7. Subtracting is the same as ADDING the OPPOSITE!
7 – 8 = 7 + (–8) which equals –1
9 – (–9) = which equals 18

8. Adding a negative number is the same as SUBTRACTING the OPPOSITE of the number!
7 + (–8) = 7 – 8 which equals –1
15 + (–8) = 15 – 8 which equals 7

9. Now you try!