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Lesson Plan
EngageNY

Secant Angle Theorem, Exterior Case

For Teachers 9th - 12th Standards
It doesn't matter whether secant lines intersect inside or outside the circle, right? Scholars extend concepts from the previous lesson plan to investigate angles created by secant lines that intersect at a point exterior to the circle....
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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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Instructional Video19:13
2
2
Flipped Math

Chords and Arcs

For Students 9th - 12th Standards
Congruence breeds congruence. Pupils learn three more circle theorems dealing with congruent chords and arcs. Learners use the theorems to find the measures of chords and arcs in circles by applying previously learned concepts in the...
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Worksheet
Curated OER

Circle Formulas

For Students 10th
Tenth graders apply various circle formulas to determine radii, diameter, circumference, area, arc length, and sector area. The two page worksheet contains twenty-five problems. Answers are not provided. 
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Lesson Plan
Curated OER

Small Angle Calculations

For Teachers 4th - 7th
Students work with circles, angles and estimating angles in the night sky. In this circles and angles lesson, students practice measuring a degree using the circumference of a circle and apply the degree to determine a way to use their...
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Worksheet
Curated OER

Angles and Arcs

For Students 10th
In this angles and arcs worksheet, 10th graders solve 8 different problems that relate to determining the measure of various angles and arcs of a circle. First, they define a central angle and the difference between a major and minor...
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Worksheet
Curated OER

Inscribed Angles

For Students 10th
In this inscribed angles instructional activity, 10th graders solve 11 different problems that are related to determining the measurement of various inscribed angles. First, they name the intercepted arc for an angle, the inscribed...
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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

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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Worksheet
Curated OER

Circles and Cylinders

For Students 10th
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.
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Worksheet
Curated OER

Quiz: Angles and Arcs in Circles - Central and Inscribed

For Students 10th - 12th
In this angles and arcs in circles activity, students determine the angle and arc measurement in a circle from given information. This one-page activity contains ten problems.
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Worksheet
Curated OER

Geometry Circles

For Students 9th - 11th
In this circle worksheet, students find the measure of identified angles. Students are given the measurement of arcs and of the central angle in a circle. This two-page worksheet contains 45 problems. Answers are provided on page two...
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Worksheet
Curated OER

Inscribed Angles

For Students 10th
In this inscribed angles activity, 10th graders solve 13 various types of problems related to inscribed angles in geometry. First, they identify a circle illustrated and each arc of the circle. They, students find the measure of each...
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Interactive
Curated OER

Angles and Arcs formed by Intersecting Chords

For Students 9th - 11th
In this angles and arcs activity, students complete a warm-up, state the formula formed by intersecting chords, and answer eight problems.  The activity includes a closing think pair share problem.
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Lesson Plan
Curated OER

Properties of Arcs, Lengths and Chords

For Teachers 9th - 11th
Students differentiate between the different properties of arcs, arc lengths, chords, and chord lengths. For this circles lesson, students calculate the arc length of a given circle, and find the measure of the inscribed angles of a...
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Lesson Plan
Curated OER

Circles and Angles

For Teachers 9th - 11th
Learners identify tangents, chords and secants. In this geometry lesson, students graph circles and identify angles created by secant lines, tangent lines and chords.
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Lesson Plan
Illustrative Mathematics

Two Wheels and a Belt

For Teachers 9th - 10th Standards
Geometry gets an engineering treatment in an exercise involving a belt wrapped around two wheels of different dimensions. Along with the wheels, this belt problem connects concepts of right triangles, tangent lines, arc length, and...
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Instructional Video19:21
2
2
Flipped Math

Intercepted Arcs

For Students 9th - 12th Standards
Intercept the class's learning on circles. Pupils learn the relationship between intercepted arcs and inscribed angles. The scholars use that information to find the relationship of angles in an inscribed quadrilateral and an angle...
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Worksheet
Curated OER

Circles Terminology Multiple Choice

For Students 9th - 12th
In this circles worksheet, students solve 10 multiple choice problems. Students answer questions about diameter and chord relationships, tangent lines to a circle, circumference, the Pi relationship, etc.
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Worksheet
Curated OER

Central and Inscribed Angles

For Students 10th
In this central and inscribed angles instructional activity, 10th graders identify and solve 20 different problems that include determining inscribed angles and intercepted arcs. First, they determine the measure of point P if the given...
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Lesson Plan
Curated OER

Arc Length Lesson

For Teachers 9th - 11th
Students find the length of the arc of a circle. In this geometry instructional activity, students calculate the length of an arc and find the measure of the central angle given the length of the arc. They convert between linear and...
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Lesson Plan
Curated OER

Cabri Jr. Inscribed Angles

For Teachers 9th - 12th Standards
Young scholars construct inscribed angles using Cabri Jr. They draw a circle on their graphing calculator, then construct an inscribed angle and measure its angle measures. Learners drag the inscribed angle around the circle. They make...
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Lesson Plan
Texas Instraments

Angles in Circles

For Teachers 9th - 12th Standards
Teach your learners how to investigate the relationship between a central angle and an inscribed angle which subtend the same arc of a circle. The dynamic nature of Cabri Jr. provides opportunity for conjecture and verification.
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Worksheet
Curated OER

Angles in Circles

For Students 10th
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...