# Ch 22: Circular Arcs, Circles & Angles

Watch online video lessons and learn about circles, circular arcs and angles and the formulas we use to measure and understand them. Take advantage of the quizzes that follow each lesson to check for understanding.

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

The lessons in this chapter explore the similarities and differences among circles, circular arcs and angles. We'll learn about formulas that help us measure these structures and look at methods of deriving equations that show various properties. Also included are practice lessons that give you experience working with some of these figures. When you've viewed all these lessons, you should be able to:

• Use the Pythagorean theorem
• Determine the measure of angles formed by tangents
• Use formulas to measure a circle's area and circumference
• Determine measurements that involve secants, tangents and chords
• Identify a polygon

Video Objective
Similarity of Circles We'll examine the like properties of all circles.
Circles: Area and Circumference This lesson explores the formulas that show the area and circumference of circles.
Circles: Inscribed Angles, Radii, Chords Here, we'll define and examine inscribed angles, chords and radii.
Practice with Inscribed Angles, Radii, Chords You'll gain experience through exercises that show the relationships between inscribed angles, radii and chords.
Inscribed and Circumscribed Figures We'll see what these figures are and look at their relationship.
Measure of an Inscribed Angle This lesson examines how to calculate the measure of an inscribed angle.
Constructing Inscribed and Circumscribed Triangles and Quadrilaterals Here, we'll see what forms an inscribed and circumscribed triangle and quadrilateral.
Proofs for Inscribed and Circumscribed Triangles and Quadrilaterals In this lesson, we'll develop proofs to show the properties of angles inscribed in a circle.
Tangent of a Circle We'll learn about forming a tangent line to a circle.
Arc Length of a Sector: Definition and Area This lesson shows what a sector is and how to find its area. You'll also learn the definition of arc length.
Arc Length and Radians We'll learn to measure arc length using radians in this lesson.
Deriving the Equation of a Circle This lesson shows us how to use the Pythagorean theorem to derive the equation of a circle.
Find the Center and Radius of a Circle by Completing the Square This video lesson explains how to derive an equation using the Pythagorean theorem as well as how to complete the square to find the circle's center and radius.
Measurements of Angles Involving Tangents, Chords and Secants We'll learn to determine the angles formed by tangents and determine the lengths of segments involved by tangents.
Measurements of Lengths Involving Tangents, Chords and Secants We'll learn to find lengths involving tangents, chords and secants.
Regular Polygons Here, we'll find out how to identify a polygon and its components.

8 Lessons in Chapter 22: Circular Arcs, Circles & Angles
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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