CK-12 Foundation
Inscribed Angles in Circles: Lesson
Circle the angles and intercept the arcs. The video introduces three theorems relating to inscribed angles in circles. Using drawings, the segment of a playlist on geometry illustrates the measure of angle along with theorems about two...
CK-12 Foundation
Angles Outside a Circle: Lesson
Understand the difference in finding angle measures. A segment of an extensive geometry playlist introduces the formula to find the measure of an angle formed outside of a circle. Using examples, the video shows how to calculate measures...
Khan Academy
Parallel Lines From Equation, Mathematics I, High School Math
Here is a fairly basic video that uses three equations, each written in slope-intercept form, to determine whether the lines are parallel. Sal graphs each equation on the same coordinate plane to show how their slopes compare. The video...
Loyola University Chicago
Math Flix: Similar Figures: Proof Using Proportions
This QuickTime movie provides an opportunity to develop the basic geometric term, similar, by checking to see if figures are proportionaly similar. As you watch and listen to the teacher and student interact it helps clarify the thinking...
Khan Academy
Khan Academy: Proof: All Circles Are Similar
Demonstrates how to use a unit circle on a coordinate grid to prove that all circles are similar. [1:34]