Circle Properties
Overview
Circles have a rich set of properties that appear across both Foundation and Higher papers. At Foundation level you need to know the standard terminology and the two key chord and tangent facts. At Higher level the circle theorems link angles, arcs, and cyclic quadrilaterals in ways that produce some of the most satisfying multi-step proofs on the paper.
This topic builds on your knowledge of angles and line properties. You will learn to name every part of a circle, prove chord and tangent relationships, and (at Higher) apply the full set of circle theorems including the alternate segment theorem and intersecting chord properties.
Objectives
- Recognise the terms 'centre', 'radius', 'chord', 'diameter', 'circumference', 'tangent', 'arc', 'sector' and 'segment' of a circle
- Understand chord and tangent properties of circles
- [Higher] Understand and use the internal and external intersecting chord properties
- [Higher] Recognise the term 'cyclic quadrilateral'
- [Higher] Understand and use angle properties of the circle including: angle subtended by an arc at the centre is twice the angle subtended at any point on the remaining part of the circumference; angle subtended at the circumference by a diameter is a right angle; angles in the same segment are equal; the sum of the opposite angles of a cyclic quadrilateral is 180 degrees; the alternate segment theorem
Mind map
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Flashcards
Quick recall practice on the facts this topic is tested on.
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Circle Properties. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- The angle between a tangent and the radius at the point of contact is: A) 45 degrees B) 60 degrees C) 90 degrees D) 180 degrees Answer: C
- A chord is 24 cm long and the radius of the circle is 13 cm. What is the perpendicular distance from the centre to the chord? A) 5 cm B) 7 cm C) 10 cm D) 12 cm Answer: A
- The angle subtended by an arc at the centre of a circle is 140 degrees. What is the angle subtended at the circumference by the same arc? A) 35 degrees B) 70 degrees C) 140 degrees D) 280 degrees Answer: B
- ABCD is a cyclic quadrilateral. Angle A = 85 degrees. What is angle C? A) 85 degrees B) 95 degrees C) 105 degrees D) 180 degrees Answer: B
- Which of the following is the region between a chord and its arc? A) Sector B) Segment C) Semicircle D) Arc Answer: B
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Recommended Books
Practice Mock Questions
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