Khan Academy
Khan Academy: Introduction to Euclidean Geometry: Language of the Circle
In this video student learn formal definition of a circle including tangent and secant lines, diameters, radii, major and minor arcs.
Khan Academy
Khan Academy: Circumference and Area of Circles: Area of a Circle
This video will show you how to solve problems dealing with the area of a circle.
Khan Academy
Khan Academy: Circles: Inscribed and Central Angles
Showing that an inscribed angle is half of a central angle that subtends the same arc.
Art of Problem Solving
Art of Problem Solving: Introduction to Circles
Video tutorial uses examples to introduce circles. [6:39]
Loyola University Chicago
Math Flix: Circle Vocabulary
This QuickTime movie provides an opportunity to learn about the vocabulary of a circle. As you watch and listen to the teacher and student interact it helps clarify the thinking behind applying this concept.
Loyola University Chicago
Math Flix: Illustrating Circle Vocabulary on the Computer
This video explains how to use drawing tools on a computer to draw circles and their parts. As you watch and listen to the teacher and student interact it helps clarify the thinking behind applying this concept. [5:59]
Khan Academy
Khan Academy: Angles in Circles Word Problem
Lindsay solves a word problem about angles as part of a circle.
Khan Academy
Khan Academy: Angle Measurement & Circle Arcs
Learn to measure angles as part of a circle.
Other
Mario's Math Tutoring: Act Math 21 Concepts to Boost Your Score
A video [48 mins, 48 sec] explaining 21 different math concepts to help students prepare for the ACT including; circumference; averages; probability; multiplication counting principle; functions; circles; percentages; factoring; rules of...
Khan Academy
Khan Academy: Circle Equations Harder Example
The video lesson from Khan Academy provides practice questions for the SAT. Watch Sal work through a harder Circle equations problem.
Khan Academy
Khan Academy: Circle Equations Basic Example
The video lesson from Khan Academy provides practice questions for the SAT. Watch Sal work through a basic Circle equations problem.
Khan Academy
Khan Academy: Circle Theorems Harder Example
The video lesson from Khan Academy provides practice questions for the SAT. Watch Sal work through a harder Circle theorems problem.
Khan Academy
Khan Academy: Circle Theorems Basic Example
The video lesson from Khan Academy provides practice questions for the SAT. Watch Sal work through a basic Circle theorems problem.
Khan Academy
Khan Academy: Ca Geometry: Circle Area Chords Tangent
Worked examples of area, chords, and tangents of circles.
Khan Academy
Khan Academy: Writing Standard Equation of a Circle
Given a circle on the coordinate plane, Sal finds its standard equation, which is an equation in the form (x-a)^2+(y-b)^2=r^2.
Sophia Learning
Sophia: Two Lines Tangent to a Circle: Lesson 4
This lesson will present how if two segments from the same point outside a circle are tangent to a circle, then they are congruent. It is 4 of 5 in the series titled "Two Lines Tangent to a Circle."
Sophia Learning
Sophia: Two Lines Tangent to a Circle: Lesson 1
This lesson will present how if two segments from the same point outside a circle are tangent to a circle, then they are congruent. It is 1 of 5 in the series titled "Two Lines Tangent to a Circle."
Sophia Learning
Sophia: Converting Between Diameter and Radius
Given this lesson and either the diameter or radius of a circle, you'll be able to calculate the other measure.
Sophia Learning
Sophia: Converting Between Diameter and Radius
Given this lesson and either the diameter or radius of a circle, you'll be able to calculate the other measure.
Sophia Learning
Sophia: What a Central Angle Is
This lesson defines the phrase central angle. Student can watch a video tutorial and then take an online quiz.
Sophia Learning
Sophia: Converting Between Diameter and Radius: Lesson 4
Given this lesson and either the diameter or radius of a circle, you'll be able to calculate the other measure. It is 4 of 10 in the series titled "Converting Between Diameter and Radius." [2:01]
Sophia Learning
Sophia: Converting Between Diameter and Radius: Lesson 7
Given this lesson and either the diameter or radius of a circle, you'll be able to calculate the other measure. It is 7 of 10 in the series titled "Converting Between Diameter and Radius." [1:56]
Sophia Learning
Sophia: Converting Between Diameter and Radius: Lesson 8
Given this lesson and either the diameter or radius of a circle, you'll be able to calculate the other measure. It is 8 of 10 in the series titled "Converting Between Diameter and Radius." [2:33]