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Instructional Video14:27
2
2
Flipped Math

Tangents to Circles

For Students 9th - 12th Standards
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...
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Lesson Plan
EngageNY

Equations for Tangent Lines to Circles

For Teachers 9th - 12th Standards
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).
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Lesson Plan
Texas Instruments

Drawing a Line Tangent to a Circle

For Teachers 9th - 12th Standards
Explore lines tangent to a circle. In this math lesson, students manipulate circles and lines on a TI calculator. They draw a circle  and analyze perpendicular lines intersecting the circle in only one place. This activity works best if...
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Activity
Illustrative Mathematics

Tangent to a Circle From a Point

For Teachers 9th - 10th Standards
Learners see application of construction techniques in a short but sophisticated problem. Combining the properties of inscribed triangles with tangent lines and radii makes a nice bridge between units, a way of using information about...
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Lesson Plan
EngageNY

Tangent Lines and the Tangent Function

For Teachers 11th - 12th Standards
Construct tangent lines and make the connection to tangent functions. An informative instructional activity reviews the geometry origins of the tangent function. Pupils use that information to determine how to construct a tangent to a...
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Lesson Plan
EngageNY

The Inscribed Angle Alternate – A Tangent Angle

For Teachers 9th - 12th Standards
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...
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Unit Plan
Mathematics Vision Project

Circles: A Geometric Perspective

For Teachers 10th - 12th Standards
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...
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Lesson Plan
EngageNY

Tangent Segments

For Teachers 9th - 12th Standards
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...
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Lesson Plan
EngageNY

Secant Lines; Secant Lines That Meet Inside a Circle

For Teachers 9th - 12th Standards
Young mathematicians identify different cases of intersecting secant lines. They then investigate the case where secant lines meet inside a circle.
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Assessment
Mathed Up!

Circle Theorems

For Students 9th - 12th
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!
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Lesson Plan
EngageNY

Graphing the Tangent Function

For Students 10th - 12th Standards
Help learners discover the unique characteristics of the tangent function. Working in teams, pupils create tables of values for different intervals of the tangent function. Through teamwork, they discover the periodicity, frequency, and...
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Lesson Plan
EngageNY

Why Call It Tangent?

For Students 10th - 12th Standards
Discover the relationship between tangent lines and the tangent function. Class members develop the idea of the tangent function using the unit circle. They create tables of values and explore the domain, range, and end behavior of the...
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Lesson Plan
Virginia Department of Education

Angles, Arcs, and Segments in Circles

For Teachers 9th - 11th Standards
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...
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Lesson Plan
EngageNY

Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams

For Teachers 9th - 12th Standards
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...
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Lesson Plan
Virginia Department of Education

Circles in the Coordinate Plane

For Teachers 9th - 11th Standards
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...
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Instructional Video16:21
2
2
Flipped Math

Secants and Tangents

For Students 9th - 12th Standards
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...
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Instructional Video13:36
2
2
Flipped Math

Unit 11 Review: Circles

For Students 9th - 12th Standards
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...
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Printables
Mr. Williams Maths

Eight Circle Theorems Page

For Teachers 8th - 12th Standards
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.
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Assessment
Inside Mathematics

Circles in Triangles

For Teachers 9th - 12th Standards
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...
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Lesson Plan
EngageNY

Properties of Tangents

For Teachers 9th - 12th Standards
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...
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Activity
101 Questions

Circle-Square

For Teachers 9th - 12th Standards
How do the area and perimeters of circles and squares compare? A clever video illustrates the change in the area of a circle and square while their total perimeter stays the same. The task is for learners to predict the point where the...
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PPT
Urbana School District

Projectile and Circular Motion, Torque

For Teachers 11th - Higher Ed Standards
Introduce your young scholars to the concepts of circular motion, projectile motion, angular speed, simple harmonic motion, torque, center of mass, centripetal force, and Hooke's Law with a 86-slide presentation. The circular motion...
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Worksheet
Mt. San Antonio Collage

Circles

For Students 9th - 12th Standards
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...
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Lesson Plan
EngageNY

Special Triangles and the Unit Circle

For Teachers 11th - 12th Standards
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...