Ch 29: Circles

About This Chapter

Use our video lessons and quizzes to help you understand circle properties and formulas. Learn to calculate measurements for radians, inscribed angles, arcs, tangents and chords.

Circles - Chapter Summary

Continue your study of plane geometry with this chapter on circles. Our experienced instructors can help you study the properties of circles and provide you with tips for proving their similarity. You can also examine the radii, tangents and chords that intersect them.

Lessons showing you how to find the lengths of chords and the inscribed angles of tangents are included as well. You can also explore the relationship between arcs and radians and practice calculating the area of a sector. Additional lessons help you apply these skills when working with inscribed and circumscribed triangles and quadrilaterals.

Instructors go on to break down the formula for a circle and show you how to write it when presented with a circle's center and radius. You can also learn how to find the center and radius when given a circle's equation by completing the square. Topics of discussion found in this chapter include:

  • Inscribed angles
  • Radii and chords
  • Tangents
  • Arc length
  • Radians

Take advantage of the illustrations included in this chapter's video lessons to get the hang of working with circles. This same material is also presented in the form of transcripts that feature links to supplementary text lessons. Use them to discover definitions of key terms and improve your understanding of the lesson topics. There are also multiple-choice quizzes you can take at any point during your studies in order to assess your grasp of the material.

6 Lessons in Chapter 29: Circles
Test your knowledge with a 30-question chapter practice test
Properties of Shapes: Circles

1. Properties of Shapes: Circles

Circles are fundamental to everything we do. But, did you know they're much more than just round shapes? In this lesson, we'll look at the various parts of circles and how they all relate.

Inscribed Angle: Definition, Theorem & Formula

2. Inscribed Angle: Definition, Theorem & Formula

Circles are all around us in our world. Inscribed angles are angles that sit inside a circle with the vertex on the circumference of the circle. Inscribed angles have a special relationship with the intercepted arc.

How to Find the Radius of a Circle: Definition & Formula

3. How to Find the Radius of a Circle: Definition & Formula

In this lesson, you will discover the definition of a radius. You will also learn how to find the radius of a circle using three different formulas based on diameter, circumference, and area.

What is a Chord in Math?

4. What is a Chord in Math?

In this lesson, you will learn what a chord of a circle is in math. You will also learn other basic parts of a circle, including the diameter and radius. Finally, you will see which of these parts is a chord and which is not.

How to Construct a Tangent of a Circle

5. How to Construct a Tangent of a Circle

It's pretty amazing what you can draw with just a straight edge and a compass! In this lesson, you'll learn how you can draw tangents of a circle, whether you are given a point on the circle or outside of the circle and if you have two circles.

Arc Length of a Sector: Definition and Area

6. Arc Length of a Sector: Definition and Area

In this lesson, we'll slice up a circle like it's a pizza and learn how to find out useful information about our slices. We'll find out the area of these sectors, or pie slices. We'll also learn about arc lengths.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
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Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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