Mr. Williams Maths
Eight Circle Theorems Page
Your learners will find these circle theorems nicely organized with diagrams included that present the geometric relationships between the circle circumference, chords, central and circumference angles and tangents.
Mathed Up!
Circle Theorems
Explore theorems involving circles. Individuals watch a video that reviews the basic parts of a circle. They learn about circle theorems and compete a worksheet of problems that use these theorems — putting their skills to work right away!
EngageNY
Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams
First angle measures, now segment lengths. High schoolers first measure segments formed by secants that intersect interior to a circle, secants that intersect exterior to a circle, and a secant and a tangent that intersect exterior to a...
Mt. San Antonio Collage
Circles
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated worksheet provides guided practice through many topics such as central angles, inscribed polygons and...
Mathematics Assessment Project
Inscribing and Circumscribing Right Triangles
High schoolers attempt an assessment task requiring them to find the radii of inscribed and circumscribed circles of a right triangle with given dimensions. They then evaluate provided sample responses to consider how to improve their...
Virginia Department of Education
Circles in the Coordinate Plane
Make the connection between the distance formula and the equation of a circle. The teacher presents a lesson on how to use the distance formula to derive the equation of the circle. Pupils transform circles on the coordinate plane and...
EngageNY
Tangent Segments
What's so special about tangents? Learners first explore how if a circle is tangent to both rays of an angle, then its center is on the angle bisector. They then complete a set of exercises designed to explore further properties and...
EngageNY
The Inscribed Angle Alternate – A Tangent Angle
You know the Inscribed Angle Theorem and you know about tangent lines; now let's consider them together! Learners first explore angle measures when one of the rays of the angle is a tangent to a circle. They then apply their newfound...
EngageNY
Properties of Tangents
You know about the tangent function, but what are tangent lines to a circle? Learners investigate properties of tangents through constructions. They determine that tangents are perpendicular to the radius at the point of tangency, and...
EngageNY
Secant Angle Theorem, Exterior Case
It doesn't matter whether secant lines intersect inside or outside the circle, right? Scholars extend concepts from the previous lesson to investigate angles created by secant lines that intersect at a point exterior to the circle....
Curated OER
Three Tangent Circles
In this tangent circles worksheet, students use pi to solve a problem involving tangent circles. This one-page worksheet contains 1 problem. The answer is provided at the bottom of the page.
Flipped Math
Secants and Tangents
Put the vertex in, put the vertex out. Pupils explore theorems about the relationships of lengths of segments and angles of line segments that intersect inside or outside the circle. Learners use the theorems to solve problems involving...
Inside Mathematics
Circles in Triangles
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
Curated OER
Tangent Lines and the Radius of a Circle
Your Geometry learners will collaboratively prove that the tangent line of a circle is perpendicular to the radius of the circle. A deliberately sparse introduction allows for a variety of approaches to find a solution.
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
Flipped Math
Tangents to Circles
Touch a circle once. Individuals watch a video and learn two theorems related to tangents and circles. The pupils then apply the theorems to find missing angle measures and lengths in figures. At the end, they practice their skills on...
Flipped Math
Unit 11 Review: Circles
Solve problems around a circle. Pupils watch a video that shows how to apply concepts about circles and related angles and segments to find solutions to word problems. Learners then review the different concepts from the unit in...
Curated OER
Tangents, Secants, and Chords
In this tangents, secants and chords worksheet, 10th graders identify and solve 48 different problems that include using 3 different theorems for defining circles. First, they determine the area of each circle with C as the center and a...
Curated OER
Segments Formed by Intersectiong Chords, Secants, and Tangents
Learners investigate the properties of segments formed which chords, secants, and tangents, intersect. The dynamic nature of Cabri Jr. allows learners to form and verify conjectures regarding segment relationships.
Curated OER
Pythagorean Theorem
In this Pythagorean theorem worksheet, 9th graders solve and complete 6 various types of problems. First, they find the length of a right-angled triangle's hypotenuse. Then, students determine which triangle is described and explain...
Illustrative Mathematics
The Lighthouse Problem
Long considered the symbol of safe harbor and steadfast waiting, the lighthouse gets a mathematical treatment. The straightforward question of distance to the horizon is carefully presented, followed by a look into the different...
Flipped Math
Intercepted Arcs
Intercept the class's learning on circles. Pupils learn the relationship between intercepted arcs and inscribed angles. The scholars use that information to find the relationship of angles in an inscribed quadrilateral and an angle...
Curated OER
Circles
In this geometry worksheet, 10th graders apply the circle segment theorems to determine the indicated segment length. The one page worksheet contains twenty problems. Answers are not provided.
Concord Consortium
Outward Bound
Just how far can I see? The short assessment question uses the Pythagorean Theorem to find the distance to the horizon from a given altitude. Scholars use the relationship of a tangent segment and the radius of a circle to find the...