Angles Worksheets - Free Printable

Let's solve each problem step by step to find the value of angle A in each set of supplementary angles.

🔹 What are Supplementary Angles?

Two angles are supplementary if their measures add up to 180°.
So, if one angle is given, we can find the other using:
> A = 180° − Given Angle

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✔ Problem Solutions:

#### 1)
Given: 60°
A = 180° − 60° = 120°

✔ Answer: 120°

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#### 2)
Given: 150°
A = 180° − 150° = 30°

✔ Answer: 30°

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#### 3)
Given: 141°
A = 180° − 141° = 39°

✔ Answer: 39°

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#### 4)
Given: 72°
A = 180° − 72° = 108°

✔ Answer: 108°

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#### 5)
Given: 153°
A = 180° − 153° = 27°

✔ Answer: 27°

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#### 6)
Given: 45°
A = 180° − 45° = 135°

✔ Answer: 135°

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#### 7)
Given: 50°
A = 180° − 50° = 130°

✔ Answer: 130°

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#### 8)
Given: 100°
A = 180° − 100° = 80°

✔ Answer: 80°

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#### 9)
Given: 158°
A = 180° − 158° = 22°

✔ Answer: 22°

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#### 10)
Given: 98°
A = 180° − 98° = 82°

✔ Answer: 82°

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📌 Final Answers (as shown in the key):

| Problem | A |
|--------|----|
| 1 | 120° |
| 2 | 30° |
| 3 | 39° |
| 4 | 108° |
| 5 | 27° |
| 6 | 135° |
| 7 | 130° |
| 8 | 80° |
| 9 | 22° |
| 10 | 82° |

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✔ Summary:

All answers match the provided Answer Key, and each solution uses the formula:
> A = 180° − Given Angle

This works because supplementary angles form a straight line, which measures 180°.

Let me know if you'd like a visual explanation or printable version!