Practice worksheet on central and inscribed angles with circle diagrams and problem-solving exercises.
Worksheet titled "Central Angles and Inscribed Angles" with diagrams of circles and problems related to naming angles and finding angle measures.
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Step-by-step solution for: Central And Inscribed Angles Worksheet - Fill Online, Printable ...
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Step-by-step solution for: Central And Inscribed Angles Worksheet - Fill Online, Printable ...
Since I can't view or access images directly, I can’t see the specific diagram or details of the problems in your uploaded image. However, based on the text you've provided, I can help you solve the Central Angles and Inscribed Angles practice problems step by step.
Let’s go through each problem logically, assuming standard circle geometry rules:
---
1. Central Angle: An angle whose vertex is at the center of the circle.
- The measure of a central angle is equal to the measure of its intercepted arc.
2. Inscribed Angle: An angle whose vertex is on the circle and whose sides are chords.
- The measure of an inscribed angle is half the measure of its intercepted arc.
3. Arc Measure: The measure of an arc is equal to the measure of its central angle.
4. Inscribed Angle Theorem:
$$
\text{Inscribed Angle} = \frac{1}{2} \times \text{Intercepted Arc}
$$
5. Opposite Angles in a Cyclic Quadrilateral:
- Sum of opposite angles = 180° (if applicable).
6. Angle formed by two chords intersecting inside a circle:
$$
\text{Angle} = \frac{1}{2}(\text{arc}_1 + \text{arc}_2)
$$
7. Tangent-Chord Angle:
$$
\text{Angle} = \frac{1}{2} \times \text{intercepted arc}
$$
---
Now, let's work through the problems as described.
---
Assuming there is a circle with center O and points A, B, C on the circumference.
#### 1. Name the chord(s)
A chord is a line segment connecting two points on the circle.
- Examples: AB, BC, AC, etc., depending on the figure.
- Likely answer: AB, BC, AC — any two points connected by a straight line within the circle.
> ✔ Answer: Chords: AB, BC, AC (or whatever segments connect two points on the circle)
---
#### 2. Name the central angle(s)
A central angle has its vertex at the center O.
- So if OA and OB are radii forming an angle at O, then ∠AOB is a central angle.
> ✔ Answer: ∠AOB, ∠BOC, ∠AOC — depending on labeled points.
---
#### 3. Name the inscribed angle(s)
An inscribed angle has its vertex on the circle.
- Example: ∠ABC, where point B is on the circle, and A and C are also on the circle.
> ✔ Answer: ∠ABC, ∠BAC, ∠ACB — any angle with vertex on the circle.
---
We’ll assume typical configurations for these types of problems.
---
#### 4. Given: m∠COB = ?; m∠CAB = ?
Let’s suppose we have a circle with center O, and points A, B, C on the circle.
If arc AB is given (say 60°), then:
- Central angle ∠AOB = arc AB = 60°
- Inscribed angle ∠ACB = ½ × arc AB = 30°
But since no values are given, perhaps the diagram shows something like:
Suppose arc AB = 80°, then:
- m∠AOB = 80° (central angle)
- m∠ACB = ½ × 80° = 40° (inscribed angle)
But without numbers, we need to guess from common setups.
Wait — maybe the diagram shows a diameter or right angles?
Alternatively, let’s suppose:
> Suppose arc AB = 100°, then:
> - m∠AOB = 100°
> - m∠ACB = 50°
But again, without values, this is speculative.
Let’s look at the next ones.
---
#### 5. m∠EBD = ?; m∠EFD = ?
This suggests a circle with points E, B, D, F.
Possibly quadrilateral inscribed in a circle.
Assume:
- ∠EBD is an inscribed angle intercepting arc ED
- ∠EFD is another inscribed angle intercepting arc ED
Then both would be half the arc.
But unless arcs are marked, we can’t compute.
Wait — perhaps it's a semicircle? Or right triangle?
Common trick: If a triangle is inscribed in a semicircle, the angle at the circumference is 90°.
So if BD is a diameter, and E is on the circle, then ∠BED = 90°.
But still, without values, we need to infer.
Perhaps the diagram shows:
- Arc ED = 120° → then inscribed angle = 60°
- But again, not sure.
Let me switch to problems 8–9, which ask for unknown values.
---
#### 8. m∠CED = ?; m∠CEA = ?
Suppose C, E, D, A are on the circle.
Maybe CE is a diameter?
Or perhaps triangle CED has some known arcs.
Without the figure, here's a common setup:
Suppose arc CD = 100°, then:
- m∠CED (inscribed) = ½ × arc CD = 50°
Similarly, if arc CA = 140°, then ∠CEA = 70°
But again, we’re guessing.
---
#### 9. m∠POQ = ?; m∠PQO = ?
Assume O is center, P and Q on circle.
Then ∠POQ is central angle → equals arc PQ.
Suppose arc PQ = 120°, then ∠POQ = 120°
Then triangle POQ: OP = OQ (radii), so isosceles.
Then ∠PQO = (180° − 120°)/2 = 30°
So possible answers:
- m∠POQ = 120°
- m∠PQO = 30°
But depends on diagram.
---
> "The figure shows a passenger airplane’s flight path on a circular radar screen as an arc of a circle centered at O."
So we have a circle with center O, and points M, T, N, K on the circle.
Let’s suppose:
#### 10. What is m∠M?
Assume ∠M is an inscribed angle.
Suppose it intercepts arc KT.
Then m∠M = ½ × arc KT
If arc KT = 100°, then ∠M = 50°
But again, need arc measure.
Wait — perhaps the diagram shows that arc MT = 120°, and ∠M is at point M?
No — if ∠M is at point M, and sides go to K and T, then it intercepts arc KT.
So yes: m∠M = ½ × arc KT
Unless it's a tangent, but likely inscribed.
#### 11. What is m∠KMT?
This is angle at M between points K, M, T.
So ∠KMT is an inscribed angle intercepting arc KT.
So m∠KMT = ½ × arc KT
Same as above.
#### 12. What is m∠NMT?
Point N, M, T — so angle at M between N and T.
So ∠NMT intercepts arc NT.
So m∠NMT = ½ × arc NT
Again, depends on arc measures.
---
Typical setup:
- Circle with center O
- Points M, T, K, N on circle
- Airplane flies from K to T, so arc KT is shown
- ∠KOT is central angle
- ∠KMT is inscribed angle
Example:
Suppose arc KT = 100°
Then:
- m∠KOT = 100° (central angle)
- m∠KMT = ½ × 100° = 50° (inscribed angle)
So:
- Problem 10: m∠M = ? → likely refers to ∠KMT = 50°
- Problem 11: m∠KMT = ? → 50°
- Problem 12: m∠NMT = ? → if arc NT = 60°, then 30°
But without actual values, we can only generalize.
---
Let’s assume a standard configuration where:
- Arc KT = 100°
- Arc NT = 60°
- O is center
Then:
#### 10. m∠M = ?
→ Assuming ∠M is ∠KMT, inscribed angle intercepting arc KT
→ m∠KMT = ½ × 100° = 50°
✔ Answer: 50°
#### 11. m∠KMT = ?
→ Same as above → 50°
✔ Answer: 50°
#### 12. m∠NMT = ?
→ Inscribed angle at M intercepting arc NT
→ m∠NMT = ½ × 60° = 30°
✔ Answer: 30°
---
| Problem | Answer |
|--------|--------|
| 1 | Chords: AB, BC, AC (example) |
| 2 | Central angles: ∠AOB, ∠BOC, ∠AOC |
| 3 | Inscribed angles: ∠ABC, ∠BAC, ∠ACB |
| 4 | m∠COB = arc CB; m∠CAB = ½ arc CB |
| 5 | m∠EBD = ½ arc ED; m∠EFD = ½ arc ED |
| 6 | m∠CED = ½ arc CD |
| 7 | m∠POQ = arc PQ; m∠PQO = (180° − arc PQ)/2 |
| 8 | m∠CED = ½ arc CD; m∠CEA = ½ arc CA |
| 9 | m∠POQ = arc PQ; m∠PQO = (180° − arc PQ)/2 |
| 10 | m∠M = 50° (example) |
| 11 | m∠KMT = 50° |
| 12 | m∠NMT = 30° |
---
Please provide the diagram details or describe:
- The positions of points A, B, C, etc.
- Any given arc or angle measures
- Whether any lines are diameters, tangents, or chords
- Specific arc measures shown
With that, I can give precise answers.
But based on typical textbook problems, the above reasoning applies.
Let me know if you can describe the diagram!
Let’s go through each problem logically, assuming standard circle geometry rules:
---
Key Concepts:
1. Central Angle: An angle whose vertex is at the center of the circle.
- The measure of a central angle is equal to the measure of its intercepted arc.
2. Inscribed Angle: An angle whose vertex is on the circle and whose sides are chords.
- The measure of an inscribed angle is half the measure of its intercepted arc.
3. Arc Measure: The measure of an arc is equal to the measure of its central angle.
4. Inscribed Angle Theorem:
$$
\text{Inscribed Angle} = \frac{1}{2} \times \text{Intercepted Arc}
$$
5. Opposite Angles in a Cyclic Quadrilateral:
- Sum of opposite angles = 180° (if applicable).
6. Angle formed by two chords intersecting inside a circle:
$$
\text{Angle} = \frac{1}{2}(\text{arc}_1 + \text{arc}_2)
$$
7. Tangent-Chord Angle:
$$
\text{Angle} = \frac{1}{2} \times \text{intercepted arc}
$$
---
Now, let's work through the problems as described.
---
Problems 1–3: Refer to the figure with O as center
Assuming there is a circle with center O and points A, B, C on the circumference.
#### 1. Name the chord(s)
A chord is a line segment connecting two points on the circle.
- Examples: AB, BC, AC, etc., depending on the figure.
- Likely answer: AB, BC, AC — any two points connected by a straight line within the circle.
> ✔ Answer: Chords: AB, BC, AC (or whatever segments connect two points on the circle)
---
#### 2. Name the central angle(s)
A central angle has its vertex at the center O.
- So if OA and OB are radii forming an angle at O, then ∠AOB is a central angle.
> ✔ Answer: ∠AOB, ∠BOC, ∠AOC — depending on labeled points.
---
#### 3. Name the inscribed angle(s)
An inscribed angle has its vertex on the circle.
- Example: ∠ABC, where point B is on the circle, and A and C are also on the circle.
> ✔ Answer: ∠ABC, ∠BAC, ∠ACB — any angle with vertex on the circle.
---
Problems 4–7: Find indicated measures
We’ll assume typical configurations for these types of problems.
---
#### 4. Given: m∠COB = ?; m∠CAB = ?
Let’s suppose we have a circle with center O, and points A, B, C on the circle.
If arc AB is given (say 60°), then:
- Central angle ∠AOB = arc AB = 60°
- Inscribed angle ∠ACB = ½ × arc AB = 30°
But since no values are given, perhaps the diagram shows something like:
Suppose arc AB = 80°, then:
- m∠AOB = 80° (central angle)
- m∠ACB = ½ × 80° = 40° (inscribed angle)
But without numbers, we need to guess from common setups.
Wait — maybe the diagram shows a diameter or right angles?
Alternatively, let’s suppose:
> Suppose arc AB = 100°, then:
> - m∠AOB = 100°
> - m∠ACB = 50°
But again, without values, this is speculative.
Let’s look at the next ones.
---
#### 5. m∠EBD = ?; m∠EFD = ?
This suggests a circle with points E, B, D, F.
Possibly quadrilateral inscribed in a circle.
Assume:
- ∠EBD is an inscribed angle intercepting arc ED
- ∠EFD is another inscribed angle intercepting arc ED
Then both would be half the arc.
But unless arcs are marked, we can’t compute.
Wait — perhaps it's a semicircle? Or right triangle?
Common trick: If a triangle is inscribed in a semicircle, the angle at the circumference is 90°.
So if BD is a diameter, and E is on the circle, then ∠BED = 90°.
But still, without values, we need to infer.
Perhaps the diagram shows:
- Arc ED = 120° → then inscribed angle = 60°
- But again, not sure.
Let me switch to problems 8–9, which ask for unknown values.
---
#### 8. m∠CED = ?; m∠CEA = ?
Suppose C, E, D, A are on the circle.
Maybe CE is a diameter?
Or perhaps triangle CED has some known arcs.
Without the figure, here's a common setup:
Suppose arc CD = 100°, then:
- m∠CED (inscribed) = ½ × arc CD = 50°
Similarly, if arc CA = 140°, then ∠CEA = 70°
But again, we’re guessing.
---
#### 9. m∠POQ = ?; m∠PQO = ?
Assume O is center, P and Q on circle.
Then ∠POQ is central angle → equals arc PQ.
Suppose arc PQ = 120°, then ∠POQ = 120°
Then triangle POQ: OP = OQ (radii), so isosceles.
Then ∠PQO = (180° − 120°)/2 = 30°
So possible answers:
- m∠POQ = 120°
- m∠PQO = 30°
But depends on diagram.
---
Find the unknown value: Problems 10–11
> "The figure shows a passenger airplane’s flight path on a circular radar screen as an arc of a circle centered at O."
So we have a circle with center O, and points M, T, N, K on the circle.
Let’s suppose:
#### 10. What is m∠M?
Assume ∠M is an inscribed angle.
Suppose it intercepts arc KT.
Then m∠M = ½ × arc KT
If arc KT = 100°, then ∠M = 50°
But again, need arc measure.
Wait — perhaps the diagram shows that arc MT = 120°, and ∠M is at point M?
No — if ∠M is at point M, and sides go to K and T, then it intercepts arc KT.
So yes: m∠M = ½ × arc KT
Unless it's a tangent, but likely inscribed.
#### 11. What is m∠KMT?
This is angle at M between points K, M, T.
So ∠KMT is an inscribed angle intercepting arc KT.
So m∠KMT = ½ × arc KT
Same as above.
#### 12. What is m∠NMT?
Point N, M, T — so angle at M between N and T.
So ∠NMT intercepts arc NT.
So m∠NMT = ½ × arc NT
Again, depends on arc measures.
---
Common Problem Type: Airplane Radar Screen
Typical setup:
- Circle with center O
- Points M, T, K, N on circle
- Airplane flies from K to T, so arc KT is shown
- ∠KOT is central angle
- ∠KMT is inscribed angle
Example:
Suppose arc KT = 100°
Then:
- m∠KOT = 100° (central angle)
- m∠KMT = ½ × 100° = 50° (inscribed angle)
So:
- Problem 10: m∠M = ? → likely refers to ∠KMT = 50°
- Problem 11: m∠KMT = ? → 50°
- Problem 12: m∠NMT = ? → if arc NT = 60°, then 30°
But without actual values, we can only generalize.
---
Final Answer (Based on Common Problems):
Let’s assume a standard configuration where:
- Arc KT = 100°
- Arc NT = 60°
- O is center
Then:
#### 10. m∠M = ?
→ Assuming ∠M is ∠KMT, inscribed angle intercepting arc KT
→ m∠KMT = ½ × 100° = 50°
✔ Answer: 50°
#### 11. m∠KMT = ?
→ Same as above → 50°
✔ Answer: 50°
#### 12. m∠NMT = ?
→ Inscribed angle at M intercepting arc NT
→ m∠NMT = ½ × 60° = 30°
✔ Answer: 30°
---
Summary of Answers (Assumed Based on Standard Problems):
| Problem | Answer |
|--------|--------|
| 1 | Chords: AB, BC, AC (example) |
| 2 | Central angles: ∠AOB, ∠BOC, ∠AOC |
| 3 | Inscribed angles: ∠ABC, ∠BAC, ∠ACB |
| 4 | m∠COB = arc CB; m∠CAB = ½ arc CB |
| 5 | m∠EBD = ½ arc ED; m∠EFD = ½ arc ED |
| 6 | m∠CED = ½ arc CD |
| 7 | m∠POQ = arc PQ; m∠PQO = (180° − arc PQ)/2 |
| 8 | m∠CED = ½ arc CD; m∠CEA = ½ arc CA |
| 9 | m∠POQ = arc PQ; m∠PQO = (180° − arc PQ)/2 |
| 10 | m∠M = 50° (example) |
| 11 | m∠KMT = 50° |
| 12 | m∠NMT = 30° |
---
To Get Exact Answers:
Please provide the diagram details or describe:
- The positions of points A, B, C, etc.
- Any given arc or angle measures
- Whether any lines are diameters, tangents, or chords
- Specific arc measures shown
With that, I can give precise answers.
But based on typical textbook problems, the above reasoning applies.
Let me know if you can describe the diagram!
Parent Tip: Review the logic above to help your child master the concept of central angles and inscribed angles worksheet.