Activity
Texas Instruments

Texas Instruments: Angles Formed by Intersecting Chords, Secants, and Tangents

For Teachers 9th - 10th Standards
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...
Activity
Texas Instruments

Texas Instruments: Inscribed Angles Intercepting the Same Arc

For Teachers 9th - 10th Standards
Students investigate the properties of angles inscribed in a circle. They use the drawing and measurement tools of Cabri Jr. to draw and measure certain angles, and establish the relationship between angles that intercept the same arc.
Handout
CK-12 Foundation

Ck 12: Geometry: Properties of a Circle Study Guide

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This study guide reviews the terminology for circles (tangent, arcs, central angles) and the equation for a circle.
Activity
Analyze Math

Analyze Math: Central and Inscribed Angles

For Students 9th - 10th Standards
The interactive tutorial examines the properties of central and inscribed angles intercepting a common arc in a circle. Learners use the applet to find central and inscribed angles.
Unknown Type
Khan Academy

Khan Academy: Quiz: Inscribed Quadrilaterals

For Students 9th - 10th Standards
Use the fact that opposite angles in an inscribed quadrilateral are supplementary to solve a few problems. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Handout
Other

Platonic Realms: Conics

For Students 9th - 10th Standards
This resource provides in depth information on the conic sections. Click on the underlined words for definitions and diagrams.
Website
Other

Antonio Gutierrez: Geometry From the Land of the Incas

For Students 9th - 10th
Discovering the properties of constructions, seeing proofs in action, and viewing problems come to life here with this wonderful use of technology in the classroom. Single steps are explained and illustrated one at a time so that the...
Lesson Plan
Khan Academy

Khan: Lesson 16: Part 2 Coordinate Geometry; Trigo and Radians; Complex Numbers

For Teachers 9th - 10th Standards
2 OF 2 FOR ADDITIONAL TOPICS IN MATH. Students will use the coordinate plane and equations of lines and circles to describe figures; create the equation of a circle given the figure or use the structure of a given equation to determine a...
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: G Co Origami Equilateral Triangle

For Teachers 9th - 10th Standards
The purpose of this task is to explore reflections in the context of paper folding. Each fold is associated with a line of reflection and understanding each step in the construction requires careful analysis of angles and of the...