# Ch 9: High School Geometry: Circular Arcs and Circles

Watch geometry video lessons and learn about locus of points, sectors of circles, tangents to circles and more. Make sure you understand key concepts of circular arcs and circles by taking the self-assessment quizzes that follow the lessons.

## Circular Arcs and Circles - Chapter Summary and Learning Objectives

What are the differences between circles and circular arcs? You can discover how to define and illustrate them in this chapter. Meet the measurement methods for arcs, inscribed angles, angles formed by tangents and the distance from a point to a circle. You can also get comfortable with discussing the relationships between circumscribed and inscribed figures. This chapter is designed to teach you:

• Locus of points in circles
• Central and inscribed angles
• Measurement of arcs and inscribed angles
• Construction of tangents to circles
• Inscribed and circumscribed figures
• Identification of regular polygons
• Formulas for circumference and area of circles
• Sector of a circle
• Arc length

Video Objective
Circular Arcs and Circles Defined Defines and illustrates a circle as well as terms related to it, such as circular arcs and semicircles. Defines locus of points. Explains how to measure the distance from a point to a circle.
Central and Inscribed Angles Defines central and inscribed angles.
Measure of an Arc Demonstrates how to measure an arc.
Measure of an Inscribed Angle Shows how to determine the measure of an inscribed angle.
Tangent of a Circle Defines the tangent of a circle. Discusses postulates about tangents. Constructs a tangent to a circle. Explores situations when there are two circles tangent to each other.
Measurements of Tangents, Angles, and Segments Explains how to find measures of angles formed by tangents and lengths of segments involving tangents.
Inscribed and Circumscribed Figures Defines inscribed and circumscribed figures. Discusses the relationships involving inscribed and circumscribed figures. Explains how to construct inscribed and circumscribed figures.
Regular Polygons Defines and illustrates a regular polygon. Explains how to identify regular polygons and their parts.
Circles: Area and Circumference Learn and apply the formulas for area and circumference of circles
Arc Length of a Sector: Definition and Area Defines a sector of a circle. Explains how to find the area of a sector. Defines arc length.

11 Lessons in Chapter 9: High School Geometry: Circular Arcs and Circles
Test your knowledge with a 30-question chapter practice test
Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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