The purpose of this task is to lead students through an algebraic approach to a well-known result from classical geometry, namely, that a point X is on the circle of diameter AB whenever angle AXB is a right angle. This consists of...

Dr. Math, in a reply to a student question, describes how a circle can be a function.

Carpenters use applications of geometry in their work, including the properties of right triangles and circles. This activity uses Cabri Jr. Geometry software to make measurements and solve problems based on carpentry situations....

[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of inscribed quadrilaterals in circles.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of inscribed angles and how to apply them.

Learn about circles with this handy reference guide. Provides a detailed definition, examples, and interactive activities that enhance further explanation. Includes links to related topics.

In this activity, students explore the properties of a unit circle and its mapping functions.

This is a proof problem, considered a "three star" geometry problem requiring knowledge of proofs and properties of circles to solve this equal area of inscribed polygons problem.

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.

This a straightforward, but interesting, project in geometry. It is a good first proof to try on your own. You should be able to figure it out by yourself, and you'll gain insight into a basic property of circles.

[Free Registration/Login may be required to access all resource tools.] Learn about the Inscribed Quadrilateral Theorem and solve problems involving quadrilaterals inscribed in circles.

When hikers and skiers go into terrain with a risk of avalanches, they take safety equipment including avalanche rescue beacons. An avalanche rescue beacon sends and receives electromagnetic field signals that travel in circular...

Students 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.

Sports such as hockey, football, basketball and tennis use balls of different sizes. Can you arrange a selection of different balls in a line each touching the next to make the shortest line? This activity offers opportunities for...

A documentary [50:38] sharing the first year of life of a humpback whale calf. From birth near Hawaii, to first months of life and the importance of bonding with the mother who teaches and protects the calf as they migrate north to...

This lesson has students discover properties of inscribed angles in a circle. Students use the Geometer's Sketchpad application for the TI-89 to construct a circle and an inscribed angle.

In this task, students are shown circle formations where an inner circle is surrounded by a set of circles and all circles are touching. In the first situation, all circles have the same diameter. In the second, the inner circle is...

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...

[Free Registration/Login Required] Students will explore quadrilaterals inscribed in circles with this interactive activity. Click 'Challenge Me' to answer a practice question.

Determine the missing angle measures of quadrilaterals inscribed in circles.

Learn more about cosine functions by exploring unit circles, and angles, how to use them, and their various applications along with some solved examples and a few interactive questions to test your understanding.

[Free Registration/Login Required] Students identify segments and lines related to circles and the properties of a tangent to a circle.

This activitie uses the power of Cabri Jr. to explore the relationship between inscribed angles and central anlges in cirles.

Why are most manhole covers round? Sure it makes them easy to roll, and slide into place in any alignment. But there's another, more compelling reason, involving a peculiar geometric property of circles and other shapes. Marc Chamberland...