Khan Academy
Khan Academy: Geometry: Triangle Angle Example 2
Shows how to find the measure of missing angles using the triangle sum theorem and vertical angles. This video also appears in the Geometry: Triangles strand. [4:55]
Khan Academy
Khan Academy: Geometry: Point Line Distance and Angle Bisectors
Proof that a point on the angle bisector is equidistant from each side of the angle and proof that a point that is equidistant from each side of the angle lies on the angle bisector. [10:57]
Khan Academy
Khan Academy: Geometry: Ca Geometry: Pythagorean Theorem, Compass Constructions
This video tutorial demonstrates solutions to problems #51-55 of the California Geometry released state test questions. Problems address proving and using the Pythagorean theorem and compass constructions. [12:35]
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 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]
Virtual Nerd
Virtual Nerd: What Are Intersecting Lines?
Two lines that cut across one another are called intersecting lines. Learn about them by watching this tutorial. [7:19]
Virtual Nerd
Virtual Nerd: What Is a Tangent Line to a Circle?
For a line to be tangent, it must have a special relationship with a circle. It can only intersect the circle at one point. Watch this tutorial for a better understanding. [3:01]
Khan Academy
Khan Academy: Geometry: Similar Example Problems
Explains how to identify and use similar triangles in order to determine unknown side lengths in two given diagrams. Each diagram also applies knowledge of angles formed when parallel lines are cut by a transversal. [7:37]
Khan Academy
Khan Academy: Geometry: Proof: Opposite Angles of Parallelogram Congruent
This video tutorial demonstrates how to prove that the opposite angles of a parallelogram are congruent based on knowledge of the special angles created when parallel lines are cut by a transversal. [4:08]
Khan Academy
Khan Academy: Geometry: Proof: Opposite Sides of Parallelogram Congruent
Demonstrates how to prove that the opposite sides of a parallelogram are congruent based on knowledge of the special angles created when parallel lines are cut by a transversal and the triangle congruency postulates. [8:30]
Khan Academy
Khan Academy: Geometry: Proof: Diagonals of Parallelogram Bisect Each Other
Demonstrates how to prove that the diagonals of a parallelogram bisect each other based on knowledge of the special angles created when parallel lines are cut by a transversal and the triangle congruency postulates. [9:06]
Virtual Nerd
Virtual Nerd: What Is a Point?
Points are needed to make lines, planes, angles, or polygons. and also for graphing. Watch this tutorial to learn about points. [3:50]
Virtual Nerd
Virtual Nerd: What Is a Transversal?
This tutorial introduces transversals and shows what happens when a transversal meets two parallel lines. [6 :22]
Virtual Nerd
Virtual Nerd: What Is a Ray?
Rays are very useful as two rays can create an angle, multiple angles can create a polygon, and by adding another dimension you get three-dimensional solids. This tutorial introduces you to rays and shows you how to name them. [4:51]
PBS
Pbs Learning Media: Real Life Math: Woodworker
Listen to a master craftsman explain many of the ways that mathematics is used in woodworking, including number operations; geometry; ratios and proportions; and measurement. In the accompanying activity, students will draw a scale...
Khan Academy
Khan Academy: Triangles: Intro to Triangle Similarity
Explains what it means for two triangles to be similar. Diagram of similar triangles is created with two parallel lines cut by two transversals.
Virtual Nerd
Virtual Nerd: What Is a Degree?
Watch this tutorial to learn what a degree is and how it relates to a circle. [3:08]
Virtual Nerd
Virtual Nerd: What Is a Plane?
This tutorial introduces planes and shows how to name them. [3:44]