EngageNY
Circles, Chords, Diameters, and Their Relationships
A diameter is the longest chord possible, but that's not the only relationship between chords and diameters! Young geometry pupils construct perpendicular bisectors of chords to develop a conjecture about the relationships between chords...
CK-12 Foundation
Length of a Chord: Distance Across a Ferris Wheel
An interactive presents two friends on a ferris wheel with the task of finding the distance between the them. Pupils create the chord between the two friends and calculate its lengths using trigonometric ratios.
Curated OER
Circles and Cylinders
In this geometry lesson, 10th graders break down a circle and identify the different parts. They discuss chords, diameter, radius, circumference, major and minor segment. There are 42 problems broken down into 5 different sections.
EngageNY
Unknown Angle Problems with Inscribed Angles in Circles
We know theorems about circles—now what? Class members prove a theorem, with half the class taking the case where a point is inside the circle and half the class taking the case where a point is outside the circle. The lesson then...
EngageNY
Secant Lines; Secant Lines That Meet Inside a Circle
Young mathematicians identify different cases of intersecting secant lines. They then investigate the case where secant lines meet inside a circle.
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...
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...
EngageNY
Arcs and Chords
You've investigated relationships between chords, radii, and diameters—now it's time for arcs. Learners investigate relationships between arcs and chords. Learners then prove that congruent chords have congruent arcs, congruent arcs have...
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...
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.
Curated OER
Circles
In this circles worksheet, 7th graders identify and complete 6 different problems that include determining various parts of a circle. First, they identify and define each circle term listed on the left. Then, students color each term...
EngageNY
Equations for Tangent Lines to Circles
Don't go off on a tangent while writing equations of tangent lines! Scholars determine the equations for tangent lines to circles. They attempt both concrete and abstract examples, such as a tangent line to the unit circle through (p, 0).
EngageNY
Geometry Module 5: Mid-Module Assessment
How can you formally assess understanding of circle concepts? Pupils take a mid-module assessment containing five questions, each with multiple parts.
EngageNY
Rectangles Inscribed in Circles
Putting a rectangular object into a circular one—didn't the astronauts on Apollo 13 have to do something like this? Learners first construct the center of a circle using perpendiculars. They then discover how to inscribe a rectangle in a...
Virginia Department of Education
Angles, Arcs, and Segments in Circles
Investigate relationships between angles, arcs, and segments in circles. Pupils use geometry software to discover the relationships between angles, arcs, and segments associated with circles. Class members use similar triangles to...
Curated OER
Congruent Chords, Parallel chords and Perpendicular Chords
In this geometry worksheet, students solve problems about congruent, parallel, and perpendicular chords and bisectors. There are 9 problems with an answer key.
Curated OER
Angles and Arcs formed by Intersecting Chords
In this angles and arcs worksheet, students complete a warm-up, state the formula formed by intersecting chords, and answer eight problems. The worksheet includes a closing think pair share problem.
Curated OER
Chords of a Circle
In this geometry worksheet, 10th graders calculate the length of a chord and the distance from the center of a circle or radius. They compare diameter, chords and radius. There are 10 questions with an answer key.
Curated OER
Geometry Review
For this geometry review worksheet, 10th graders solve and complete 33 different problems that include identifying various geometric figures and parts of a circle. First, they find the radius of each circle given its diameter. Then,...
Curated OER
Angles in Circles
In this angles in circles worksheet, 10th graders solve 10 different problems that include tangents and chords and intersecting chords. First, they find x when given 2 intersecting chords. Then, students determine x given the diameter...
Curated OER
Circles
In this circles instructional activity, 10th graders solve 10 different problems that include determining the chords, secants, and tangents of circles shown. First, they determine 4 different line segments given a circle with secants and...
Curated OER
Perpendicular Segments in a Circle
High schoolers explore the concept of circles as they construct a circle using a program such as Cabri Jr. Learners construct a chord and a diameter that are perpendicular, then measure the bisected chord and notice that both sides of...
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 students to form and verify conjectures regarding segment relationships.
Curated OER
Tangents, Secants, and Chords
For 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...