Worksheet for practicing addition of integers with problems involving positive and negative numbers.

Let's solve each of the integer addition problems step by step. The key rule to remember when adding integers is:

- Same signs: Add the absolute values and keep the common sign.
- Different signs: Subtract the smaller absolute value from the larger one, and take the sign of the number with the larger absolute value.

---

Left Column:

1. 9 + (–11)
Different signs: |9| = 9, |–11| = 11 → 11 – 9 = 2 → negative (since –11 has larger absolute value)
= –2

2. 7 + (–11)
Different signs: 11 – 7 = 4 → negative
= –4

3. –2 + 11
Different signs: 11 – 2 = 9 → positive
= 9

4. –12 + 2
Different signs: 12 – 2 = 10 → negative
= –10

5. 8 + (–10)
Different signs: 10 – 8 = 2 → negative
= –2

6. –6 + (–12)
Same signs: 6 + 12 = 18 → negative
= –18

7. 9 + (–9)
Same absolute values, opposite signs → cancel out
= 0

8. 11 + 4
Same signs: 11 + 4 = 15 → positive
= 15

9. –12 + 10
Different signs: 12 – 10 = 2 → negative
= –2

10. 8 + 6
Same signs: 8 + 6 = 14 → positive
= 14

11. –8 + 12
Different signs: 12 – 8 = 4 → positive
= 4

12. 1 + 11
Same signs: 1 + 11 = 12 → positive
= 12

13. 10 + (–3)
Different signs: 10 – 3 = 7 → positive
= 7

---

Right Column:

1. 12 + 11
Same signs: 12 + 11 = 23 → positive
= 23

2. –7 + 8
Different signs: 8 – 7 = 1 → positive
= 1

3. –1 + 12
Different signs: 12 – 1 = 11 → positive
= 11

4. –9 + (–2)
Same signs: 9 + 2 = 11 → negative
= –11

5. 6 + 8
Same signs: 6 + 8 = 14 → positive
= 14

6. 3 + (–11)
Different signs: 11 – 3 = 8 → negative
= –8

7. 11 + (–10)
Different signs: 11 – 10 = 1 → positive
= 1

8. –12 + 6
Different signs: 12 – 6 = 6 → negative
= –6

9. –4 + (–11)
Same signs: 4 + 11 = 15 → negative
= –15

10. –1 + 4
Different signs: 4 – 1 = 3 → positive
= 3

11. –12 + (–8)
Same signs: 12 + 8 = 20 → negative
= –20

12. –10 + 10
Same absolute values, opposite signs → cancel out
= 0

---

✔ Final Answers:

Left Column:
1. –2
2. –4
3. 9
4. –10
5. –2
6. –18
7. 0
8. 15
9. –2
10. 14
11. 4
12. 12
13. 7

Right Column:
1. 23
2. 1
3. 11
4. –11
5. 14
6. –8
7. 1
8. –6
9. –15
10. 3
11. –20
12. 0

---

✔ Answer Key (All):

```
9 + (–11) = –2 12 + 11 = 23
7 + (–11) = –4 –7 + 8 = 1
–2 + 11 = 9 –1 + 12 = 11
–12 + 2 = –10 –9 + (–2) = –11
8 + (–10) = –2 6 + 8 = 14
–6 + (–12) = –18 3 + (–11) = –8
9 + (–9) = 0 11 + (–10) = 1
11 + 4 = 15 –12 + 6 = –6
–12 + 10 = –2 –4 + (–11) = –15
8 + 6 = 14 –1 + 4 = 3
–8 + 12 = 4 –12 + (–8) = –20
1 + 11 = 12 –10 + 10 = 0
10 + (–3) = 7
```

Let me know if you'd like this in a printable format or need help understanding any specific problem!