CK-12 Foundation
Perpendicular Bisectors: Lesson
Get right up and split it in half. Using a diagram, the video provides the definition of a perpendicular bisector. The portion in a playlist on basic geometry explains perpendicular bisector of a segment and of triangle sides properties.
Krista King Math
Naming Simple Geometric Figures
Mathematicians use notation for efficiency, so make your classes more efficient! The instructor explains the definition and notation for key elements of geometry such as points, lines, and planes. This is the 37th lesson is a series of...
CK-12 Foundation
Altitudes: Examples
Find the location of altitudes—from any elevation! The video presents the definition of an altitude of a triangle. By drawing examples, the segment of a larger geometry playlist highlights the location of altitudes of various triangle...
Flipped Math
Parallelogram Properties
Provide pupils with problems on applying properties of parallelograms. The second of seven installments in the Geometry - Quadrilaterals and Polygons unit focuses on parallelograms. Viewers of the instructional video learn about the...
Virtual Nerd
What is an Ellipse?
This video answers the question, What is an ellipse? It gives a definition of an ellipse, shows the ellipses relation of a plane to a cone, and the names of different parts of the ellipse.
Curated OER
How Do You Find a Missing Angle in a Triangle?
The interior angles of any and ALL triangles adds up to 180 degrees. So if given two of the angle degrees, is it possible to find the value of the third angle? Yes! Use the triangle sum theorem to solve for the missing angle. Watch this...
Curated OER
How Do You Translate a Polynomial Function Vertically?
Want to move a graphed function up or down? This is called a function translation. This video looks at translating a cubic function up three units. It considers the function in standard form, the graph of the function, and a table of...
Virtual Nerd
Virtual Nerd: What Is a Line Segment?
Take a look at this tutorial to learn about line segments, how to name them, and what the midpoint of a line segment is. [3:13]
Virtual Nerd
Virtual Nerd: What Are the Endpoints of a Line Segment?
Watch this tutorial to learn about the endpoints of a line segment. [1:18]
Khan Academy
Khan Academy: Measuring Line Segments
In this example of measuring a line segment, the numbers span across the positive and negative. Remember, line segments and points are the foundations of geometry, so this is an important concept.
Khan Academy
Khan Academy: Introduction to Euclidean Geometry: Lines, Line Segments, and Rays
In this video the students explore the difference between lines, line segments, and rays.
Khan Academy
Khan Academy: Geometry: Lines, Line Segments, and Rays
Compares qualities of line segments, lines, and rays. Practice problems available. [3:38]
Khan Academy
Khan Academy: Geometry: Two Column Proof Showing Segments Are Perpendicular
In this video tutorial [11:06], the instructor shows how to construct a two-column proof using triangle congruence postulates to prove that two line segments are perpendicular.
Khan Academy
Khan Academy: Geometry: Language and Notation of Basic Geometry
Explains terms and notation of basic elements of geometry. [12:57]
Khan Academy
Khan Academy: Introduction to Euclidean Geometry
In this video students gain an understanding of basic ideas in geometry and how we represent them with symbols.
Khan Academy
Khan Academy: Geometry: Congruent Triangle Proof Example
Demonstrates how to use triangle congruency to prove that a given point is the midpoint of a given line segment. The proof is written in the form of a two-column proof. Practice problems available. [5:46]
Virtual Nerd
Virtual Nerd: What's the Midpoint Formula?
The midpoint of a line segment is the point located midway between the endpoints of the line segment. Take a look at this tutorial to learn about the midpoint. [1:59]
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...
Loyola University Chicago
Math Flix: Congruency
This QuickTime movie provides an opportunity to learn about the basic geometric term congruency. 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: Similar Figures: Cross Multiplication
This QuickTime movie provides an opportunity to develop the basic geometric term, similar, by using cross multiplication to see if figures are similar. As you watch and listen to the teacher and student interact it helps clarify the...
Loyola University Chicago
Math Flix: Similar Figures: Ratio
This QuickTime movie provides an opportunity to develop the basic geometric term, similar, by using a ratio to see if figures are similar. As you watch and listen to the teacher and student interact it helps clarify the thinking behind...