Khan Academy: Geometry: Language and Notation of Basic Geometry

Formally defines a circle and different parts of a circle. Identifies the proper notation for naming different parts of a circle. [11:12]

The video tutorial [12:21] demonstrates solutions to problems #66-70 of California Geometry released state test questions. Problems address basic trigonometry ratios, 30-60-90 triangles.

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]

Demonstrates solutions to problems #56-60 of the California Geometry released state test questions. Problems address compass constructions, slope of perpendicular lines, and using the distance formula. [12:49]

Demonstrates how to find the area of an equilateral triangle inscribed in a circle by applying the area formula for a circle and Heron's formula. Some basic trigonometry (SOHCAHTOA) is also used. [11:38]

This video illustrates how the exponential form of a complex number can be helpful in finding the complex roots of a number. The process is shown both algebraically and graphically using x^3 = 1 as a simple example. [11:53]

This video tutorial [5:07] demonstrates how to use the basic properties of parallelograms, rectangles, squares, rhombi, and trapezoids to determine what are the possible ways to name a given geometric shape.

Introduction to Euclid, Euclid's Elements, and Euclidean geometry. [8:23]

Proof that the sum of the angles in a triangle is 180 using the relationship of angles formed when parallel lines are cut by a transversal. This video also appears in the Geometry: Triangles strand. [6:31]

Demonstrates how to solve five different problems from a released California Geometry state test that involve finding the measures of angles in different polygons. This video also appears in the Geometry: Worked Examples section. [10:58]