CK-12 Foundation
Ck 12: Geometry: Angles on and Inside a Circle
[Free Registration/Login may be required to access all resource tools.] Solve problems containing angles on or inside a circle.
Mangahigh
Mangahigh: Shape: Radius and Tangent Rule for Circles
Determine the rules for radius and tangents of circles.
CK-12 Foundation
Ck 12: Tangent Lines
[Free Registration/Login Required] Students can adjust the size of the circle to explore the tangent lines. Click learn more to watch a video and click challenge me to answer a practice question.
CK-12 Foundation
Ck 12: Segments From Secants and Tangents
[Free Registration/Login Required] Students will adjust points to explore secants and tangents of circles. Click learn more to watch a video and click challenge me to answer a practice question.
Mangahigh
Mangahigh: Pyramid Panic: Basic Shapes to Advanced Geometry
Guide a mummy safely through the burial chambers of a pyramid as you solve length and area problems in basic to advanced geometry. There are four game zones that deal with circles and triangles, quadrilaterals, the Pythagorean Theorem,...
Geometry Help
Geometry Help: Chords
Explains the basic concept of chords with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
ClassFlow
Class Flow: Circles Geometry
[Free Registration/Login Required] Students identify segments and lines related to circles and the properties of a tangent to a circle.
Ministerio de Educacion, Cultura y Deporte (Spain)
Cnice: Relacion De Ejercicios Interactivos.
In Spanish. Interactive activities online on various geometric and trigonometric concepts such as area, perimeter, secants, tangents, etc. A terrific resource for students. Site is organized acoording to shape. (triangle, quadrilaterals,...
Oswego City School District
Regents Exam Prep Center: Formulas for Angles in Circles
Formulas and illustrations show the different kinds of angles created by intersecting tangents, secants, radii, and in combination.
Khan Academy
Khan Academy: Challenge Problems: Circumscribing Shapes
Solve two challenging problems that apply properties of tangents to find the perimeter of a circumscribing shape.
Other
Ctte: Geometer's Sketch Pad Activities
This site offers numerous activities for middle school and high school students to explore using Geometer's Sketch Pad.