Texas Instruments
Texas Instruments: Angles Formed by Intersecting Chords, Secants, and Tangents
In this activity, students will investigate properties of angles and arcs formed when chords, secants, and tangents intersect and intercept arcs in a circle. They discover several important theorems concerning circles and arc sizes. They...
Texas Instruments
Texas Instruments: Chords, Secants, and Tangents
Young scholars construct chords, secants, and tangents. From those constructions, they develop a deeper understanding of the terms, as well as explore certain properties of the constructions.
Texas Instruments
Texas Instruments: Segments Formed by Intersecting Chords, Secants, and Tangents
This activity is designed to help students discover several important theorems concerning lengths of segments formed by intersecting chords, secants, and tangents.
CK-12 Foundation
Ck 12: Geometry: Circles: Segments and Lengths Study Guide
This study guide on circles covers some vocabulary and theorems about segments and lengths. It is available for download with free registration.
Texas Education Agency
Texas Gateway: Making Conjectures About Circles and Segments
Given examples of circles and the lines that intersect them, the student will use explorations and concrete models to formulate and test conjectures about the properties and relationships among the resulting segments.
Oswego City School District
Regents Exam Prep Center: Circles, Segments, and Area
A wealth of resources to supplement instruction on parts of the circle. Find lessons describing chords, tangents, secants, and segments, as well as related practice quizzes and classroom activities.
Math Open Reference
Math Open Reference: Circles
A complete reference guide to circles including parts, angles, and arcs. It provides definitions and interactive activities that enhance further explanation.
Math Planet
Math Planet: Geometry: Advanced Information About Circles
Provides advanced information about circles through the use of examples and a brief video lesson. [1:00]