1. Learn to add integers.

2. Adding Integers
To add two integers with the same sign, find the sum of their absolute values. Use the sign of the two integers.
To add two integers with different signs, find the difference of their absolute values. Use the sign of the integer with the greater absolute value.

3. The integers are the set of whole numbers and their opposites
The integers are the set of whole numbers and their opposites. Including zero.
The whole numbers are the counting numbers and zero: 0, 1, 2, 3,
Remember!

4. The opposite of a number is the same
distance from 0 on a number line as the
original number. Zero is its own opposite.
–4 and 4 are opposites –4 4 • •
–5–4–3–2–1 0
Negative integers
Positive integers
0 is neither positive
nor negative

5. A number’s absolute value is its distance from 0 on a number line.
They are always positive or zero.
The symbol is read as “the absolute value of.” For example -3 is the absolute value of -3.
Reading Math

6. Example 1: Modeling Integer Addition
Use a number line to find each sum.
–7 + (–4)
+(–4) –7 2
–14 –12 –10 –8 –6 –4 –
Start at 0. Move left 7 spaces. Then move left
4 more spaces.
–7 + (–4) = –11

7. Example 2: Modeling Integer Addition
Use a number line to find each sum. – 19
–12
–12 –10 –8 –6 –4 –
Start at 0. Move left 12 spaces. Then move
right 19 spaces.
– = 7

8. Insert Lesson Title Here
Example 3
Use a number line to find each sum.
–4 + (–5)
+(–5) –4 2
–14 –12 –10 –8 –6 –4 –
Start at 0. Move left 4 spaces. Then move left
5 more spaces.
–4 + (–5) = –9

9. Insert Lesson Title Here
Example 4
Use a number line to find each sum.
–7 + 12 12 –7
–12 –10 –8 –6 –4 –
Start at 0. Move left 7 spaces. Then move
right 12 spaces.
– = 5

10. Example 5: Adding Integers Using Absolute Values
Find each sum.
–4 + 8
The signs are different. Find the difference of the absolute values.
–4 + 8
Think: 8 – 4 = 4.
Use the sign of the integer with the
greater absolute value. 4

11. Example 6: Adding Integers Using Absolute Values
Find each sum.
23 + (–35)
The signs are different. Find the difference of the absolute values.
23 + (–35)
Think: 35 – 23 = 12.
Use the sign of the integer with the
greater absolute value.
–12

12. Insert Lesson Title Here
Example 7
Find each sum.
–5 + 3
The signs are different. Find the difference of the absolute values.
–5 + 3
Think: 5 – 3 = 2.
Use the sign of the integer with the
greater absolute value. –2

13. Insert Lesson Title Here
Example 8
Find each sum.
–13 + (–24)
The signs are the same. Find the sum of the absolute values.
–13 + (–24)
Think: = 37.
–37
Use the sign of the two integers.

14. Insert Lesson Title Here
Example 9
The French Club was raising money for a trip to Washington D.C. Their car wash raised $730. They had expenses of $52. Use integer addition to find the club’s total profit or loss.
730 + (–52)
Use negative for the expenses.
Find the differences of the
absolute values.
730 – 52
678
The answer is positive.
The club earned $678.

15. Insert Lesson Title Here
Exit Ticket
Use a number line to find the sum.
1. –7 + (–6)
Find each sum.
2. – (–9)
3. – (–3)
4. Evaluate x + y for x = –2 and y = –15.
–13 2
–14 –12 –10 –8 –6 –4 –
–20
–17

16. Insert Lesson Title Here
The math club’s income from a bake sale was $217. Advertising expenses were $32. Use integer addition to find the club’s total profit or loss?
$185 profit