This answer key provides the correct solutions for the Negative Numbers Addition and Subtraction 1 worksheet, helping teachers and parents grade student assignments quickly.

You’ve uploaded an answer key for a math worksheet titled “Negative Numbers: Addition and Subtraction — Math Worksheet 1”. The task is to solve the problems shown, but since this is already the answer key, all the answers are filled in.

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✔ Let’s go through each problem and explain the solution:

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🔢 Addition & Subtraction with Negative Numbers Rules Recap:

- Adding a negative = subtracting a positive → `a + (-b) = a - b`
- Subtracting a negative = adding a positive → `a - (-b) = a + b`
- When signs are the same → add absolute values, keep sign.
- When signs are different → subtract smaller from larger, keep sign of larger number.

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## 🧮 Problem-by-Problem Solutions:

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1. 8 + (–1) = 7
→ Adding a negative is like subtracting: 8 – 1 = 7 ✔

2. 0 – (–4) = 4
→ Subtracting a negative = adding: 0 + 4 = 4 ✔

3. (–4) + (–8) = –12
→ Both negative → add absolute values (4+8=12), keep negative sign → –12 ✔

4. 9 + (–4) = 5
→ Different signs → 9 – 4 = 5, positive since 9 > 4 ✔

5. (–8) + 7 = –1
→ Different signs → 8 – 7 = 1, negative since |–8| > 7 → –1 ✔

6. 3 + (–4) = –1
→ Different signs → 4 – 3 = 1, negative since |–4| > 3 → –1 ✔

7. (–5) + (–2) = –7
→ Both negative → 5 + 2 = 7 → –7 ✔

8. 9 + (–5) = 4
→ Different signs → 9 – 5 = 4, positive since 9 > 5 ✔

9. 3 × (–2) = –6 ← ❗ Wait — this is multiplication!
But the worksheet says “Addition and Subtraction” — maybe typo?
Actually, looking at the image again — it's written as `3×(-2)` — so it’s multiplication.
→ Positive × negative = negative → 3×2=6 → –6
✘ But the answer key says –1 — that’s incorrect.

⚠️ Correction Needed:
> 3 × (–2) = –6, not –1.

This appears to be an error in the answer key.

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10. 9 + (–2) = 7
→ 9 – 2 = 7 ✔

11. (–8) + (–2) = –10
→ Both negative → 8+2=10 → –10 ✔

12. (–5) + (–9) = –14
→ 5+9=14 → –14 ✔

13. (–1) + (–1) = –2
→ 1+1=2 → –2 ✔

14. (–8) + (–5) = –13
→ 8+5=13 → –13 ✔

15. (–3) + (–7) = –10
→ 3+7=10 → –10 ✔

16. (–1) + 2 = 1
→ Different signs → 2 – 1 = 1, positive since 2 > 1 ✔

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## 📝 Summary:

✔ Most answers are correct.

✘ One error found:
> Problem 9: 3 × (–2) = –6 (not –1)

If this was intended to be addition, then it should be `3 + (–2) = 1`, but it’s clearly written as multiplication (`×`).

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## 🎯 Final Answer:

All problems solved correctly except #9, which should be:

> 3 × (–2) = –6

The rest are correct per standard integer arithmetic rules.

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📌 Note for Teacher/Student:
If this is meant to be strictly *addition and subtraction*, then problem #9 might be misprinted. If it’s intentional multiplication, then the answer key is wrong there.

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✔ Completed Correctly (with correction):

```
8 + (–1) = 7
0 – (–4) = 4
(–4) + (–8) = –12
9 + (–4) = 5
(–8) + 7 = –1
3 + (–4) = –1
(–5) + (–2) = –7
9 + (–5) = 4
3 × (–2) = –6 ← CORRECTED
9 + (–2) = 7
(–8) + (–2) = –10
(–5) + (–9) = –14
(–1) + (–1) = –2
(–8) + (–5) = –13
(–3) + (–7) = –10
(–1) + 2 = 1
```

✔ Total Correct (after correction): 16/16

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