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...
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.
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...
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...
EngageNY
Tangent Lines and the Tangent Function
Construct tangent lines and make the connection to tangent functions. An informative activity reviews the geometry origins of the tangent function. Pupils use that information to determine how to construct a tangent to a circle from a...
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...
EngageNY
Properties of Trigonometric Functions
Given a value of one trigonometric function, it is easy to determine others. Learners use the periodicity of trigonometric functions to develop properties. After studying the graphs of sine, cosine, and tangent, the instructional...
CK-12 Foundation
Unit Circle: Medieval Castle Defense
Who needs a plan — let trigonometry protect you! Pupils determine the angle of an approaching enemy to a village wall. The scholars determine the exact value of trigonometric functions for the angle. Class members use trigonometry to...
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
Tangents and Circles
In this tangents and circles worksheet, 10th graders solve 10 different problems that include various tangents and circles. First, they determine in each diagram whether the segments shown are tangents or not. Then, students determine...
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.
Flipped Math
Unit Circle and Radians
Measure angles is easy as pi. Pupils review special right triangles to find exact values for trigonometric functions. Scholars learn about radians and how they connect to measurements in degrees. They find exact and approximate values of...
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...
Illustrative Mathematics
Satellite
Learners practice relating rules of trigonometry and properties of circles. With a few simplifying assumptions such as a perfectly round earth, young mathematicians calculate the lengths of various paths between satellite and...
CK-12 Foundation
Tangent Graphs: Slope and Angle
Learning about tangents doesn't have to be a slippery slope. Pupils drag a point around a unit circle to see how angle affects the slope of a line. They individually answer a set of challenge questions to come to the conclusion that...
Curated OER
Geometry of Circles - Week 7 (Area & Circumference)
In this circle worksheet, students solve problems involving the circumference, area and arc length in a circle. They explore the union of circles and semicircles, as well as the line segments tangent to the circle. This two-page...
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!
Mathematics Assessment Project
Circles in Triangles
Circles, and triangles, and tangents, oh my! In the assessment task, learners first answer questions leading to the radius of an inscribed circle for a given right triangle. They then use the result to independently determine the...
CK-12 Foundation
Trigonometric Functions and Angles of Rotation: The Triangle in the Circle
Go around the unit circle and create triangles. Pupils move a point around the unit circles to visualize the triangle associated with the angle in standard position. The three main trigonometric functions are defined in terms of the legs...
CK-12 Foundation
Reference Angles and Angles in the Unit Circle: Exploring Reference Angles
A steal of a deal — get four angles for the value of one. An interactive resource allows individuals to visualize all four angles that have the same reference angle. Pupils answer questions by using the interactive to create the...
CK-12 Foundation
Trigonometric Functions of Angles Greater than 360 Degrees: Snowboarding
Spin through the trigonometric functions. Scholars determine the angle of rotation a snowboarding snowman makes at various distances in his jump. The class members then calculate the values of trigonometric functions for those angles.
Curated OER
Arc and Angles Formed by Secants and Tangents
In this calculus worksheet, students solve problems by finding the line of tangency and measure of the arcs and angles form by a secant line. There are 9 questions.
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
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.