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...
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 activity then...
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 activity provides guided practice through many topics such as central angles, inscribed polygons...
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...
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...
Curated OER
Circles and Angles
Young scholars identify tangents, chords and secants. In this geometry lesson, students graph circles and identify angles created by secant lines, tangent lines and chords.
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...
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.
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.
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...
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...
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.
West Contra Costa Unified School District
Arcs and Angles
Noah didn't construct this kind of arc. High school scholars first explore how angles can be formed in circles. They then learn relationships between angles and arcs by conducting an exploratory activity where they position and draw arcs...
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.
Virginia Department of Education
Arc Length and Area of a Sector
What do skateboarding and baked goods have in common with math? You can use them to connect half-pipe ramps and cakes to arcs and sectors. Pupils compare the lengths of three different ramp options of a skate park. They calculate the...
Curated OER
Circles
In this circles worksheet, 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 chords with...
Curated OER
Angles in Circles
For 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
Arcs and Chords Homework
In this geometry worksheet, high schoolers examine a circle with chords and apply formulas to solve for the missing segments or arc. There are 9 questions.
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...
Curated OER
Arcs and Angles Formed by a Tangent and a Chord
In this math worksheet, 10th graders solve problems involving a tangent line intersection the arc and forming various angles. There are 6 problems to be solved.
Curated OER
Secants, Tangents and Arcs
Learners identify chords and angles. In this geometry lesson, students calculate the length of the chords inside and outside of-the circle. They differentiate between tangent and secant lines.
Curated OER
Inscribed and Central Angles in a Circle
In this geometry worksheet, students find the missing angle that is inscribed inside of a circle. They define vocabularies related to the circle. There are 17 questions.