Texas Instruments
Texas Instruments: Inscribing a Circle in a Triangle
In this activity, students bisect the angles of a triangle and find the incenter of the triangle. They find the distance from the incenter to the side of the triangle and use it as radius. With the incenter as the center, they inscribe a...
Khan Academy
Khan Academy: Inscribed Shapes
Find missing angles and lengths in inscribed shapes. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Walter Fendt
Walter Fendt: Thales' Circle
A short interactive activity to prove that a triangle inscribed in a semicircle is right-angled.
CK-12 Foundation
Ck 12: Geometry: Inscribed Quadrilaterals in 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.
Khan Academy
Khan Academy: Quiz: Inscribed Quadrilaterals
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.
Khan Academy
Khan Academy: Challenge Problems: Inscribed Shapes
Solve three challenging problems that apply properties of inscribed shapes to find an arc length or a missing angle.
Khan Academy
Khan Academy: Inscribed Quadrilaterals
Use the fact that opposite angles in an inscribed quadrilateral are supplementary to solve a few problems.
Khan Academy
Khan Academy: Tangents of Circles Problems
Solve problems related to tangents of circles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Tangents of Circles Problems
Solve problems related to tangents of circles.
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Ingulos en Una Circumferencia
In Spanish. This site discusses the angles relative to the circles. It defines the concept of central angle, inscribed, interior, exterior and some important geometric outcomes and applications which uses these concepts.
CK-12 Foundation
Ck 12: Geometry: Chords in Circles
[Free Registration/Login may be required to access all resource tools.] In this lesson, students apply chord theorems. Students examine guided notes, review guided practice, watch instructional videos and attempt practice problems.
Mangahigh
Mangahigh: Shape: Quadrilaterals Inscribed in Circles
Determine the missing angle measures of quadrilaterals inscribed in circles.
Illustrative Mathematics
Illustrative Mathematics: G Gpe.5 Triangles Inscribed in Circle
In this task, students use ideas about linear functions to determine when certain angles are right angles. They use the fact that two lines (if not vertical or horizontal) are perpendicular when their slopes are inverse reciprocals, as...
CK-12 Foundation
Ck 12: Inscribed Quadrilaterals in Circles
[Free Registration/Login Required] Students will explore quadrilaterals inscribed in circles with this interactive activity. Click 'Challenge Me' to answer a practice question.
Math Words
Mathwords: Inscribed Circles
Mathwords provides an explanation and a diagram of an inscribed circle. By clicking on any of the highlighted words, you will learn about related terms.
Texas Instruments
Texas Instruments: Segments Formed by Intersecting Chords, Secants, and Tangents
This activity is designed to help learners discover several important theorems concerning lengths of segments formed by intersecting chords, secants, and tangents.
Texas Instruments
Texas Instruments: Chords, Secants, and Tangents
Learners 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.
Illustrative Mathematics
Illustrative Mathematics: G Co Classifying Triangles
The goal of this task is to help students synthesize their knowledge of triangles where only two of the vertices have been given. They will need to know that a triangle inscribed in a circle, with a diameter of the circle as one side, is...
Illustrative Mathematics
Illustrative Mathematics: G Co Origami Equilateral Triangle
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...
CK-12 Foundation
Ck 12: Geometry: Segments From Chords
[Free Registration/Login may be required to access all resource tools.] Looks at how to apply the Intersecting Chords Theorem.
Math Open Reference
Math Open Reference: Thales' Theorem
Learn about Thales' Theorem with this handy reference guide. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Illustrative Mathematics
Illustrative Mathematics: G C Locating Warehouse
You have been asked to place a warehouse so that it is an equal distance from three roads on a map. Students must fold a paper so that this point is where two folds intersect, and they must explain why their construction works and why...