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,...
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...
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 high schoolers to form and verify conjectures regarding segment relationships.
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
Tangents, Secants, and Chords
In this tangents, secants and chords instructional activity, 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...
Curated OER
Chors, Secants, Tangents
Pupils identify the relationship between chords, secants and circles. For this geometry lesson, students calculate the length of the chords. They sketch the secant lines on a circle.
Curated OER
Segment Formulas Homework
In this geometry worksheet, students examine three different diagrams and apply the appropriate formulas to each of the following situations: two chords, a tangent and a secant, and two secants. There are 17 questions to solve for the...
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...
Curated OER
Circles
In this circles learning exercise, 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...
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
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.
Curated OER
Intersecting Lines and Segments of Measures
Mathematicians measure intersecting lines-and circles, and create chords. In this geometry lesson, students explore interrior and exterior chords created by tangent and secant lines. These segments can be inside the circleor outside the...
Curated OER
Relationship between tangent, secant side length
In this calculus worksheet, students calculate the relationship between a line of tangency and a secant side length. They are given the formulas to solve their problems. There are 9 problems.
Curated OER
Tangents to a Circle
Students construct tangent lines. In this geometry lesson plan, students identify the point of tangency, secant and tangent lines. They graph the lines on the Ti and make observations.
Curated OER
Measuring the Earth
Young scholars identify types of arcs and angles in a circle, find the measure of arcs and angles, and solve real world problems involving lengths of segments in circles, lengths, and areas.
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...
Curated OER
Circles and Angles
Students 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
Circle Packing
Students identify different parts and properties of circles. In this geometry lesson, students identify the radius, diameter, semicircle and inscribed angle of a circle. They identify the tangent lines to 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
Understanding Fundamental Trigonometric Identities
Young scholars are introduced to the basic trigonometric identities. Using a diagram, they discover why the parts of the unit circle as named as they are and use equations to finalize the Pythagorean trigonometric identities. They also...
Oswego City School District
Regents Exam Prep Center: Circles, Segments, and Area
A wealth of resources to supplement instruction on parts of the circle. Find lessons describing chords, tangents, secants, and segments, as well as related practice quizzes and classroom activities.
Texas Education Agency
Texas Gateway: Making Conjectures About Circles and Segments
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.
CK-12 Foundation
Ck 12: Geometry: Circles: Segments and Lengths Study Guide
This study guide on circles covers some vocabulary and theorems about segments and lengths. It is available for download with free registration.
CK-12 Foundation
Ck 12: Geometry: Segments From Secants and Tangents
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to solve for missing segments created by a tangent line and a secant line intersecting outside a circle.