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Circle basics

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Circles glossary
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Radius, diameter, circumference & π
(Opens a modal)
Proof: all circles are similar
(Opens a modal)

Arc measure

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Intro to arc measure
(Opens a modal)
Finding arc measures
(Opens a modal)
Finding arc measures with equations
(Opens a modal)
Practice
Arc measureGet 3 of 4 questions to level up!
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Arc measure with equationsGet 3 of 4 questions to level up!
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Arc length (from degrees)

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Arc length from subtended angle
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Subtended angle from arc length
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Challenge problems: Arc length 1
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Challenge problems: Arc length 2
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Practice
Arc lengthGet 3 of 4 questions to level up!
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Quiz 1

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Introduction to radians

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Intro to radians
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Radians & degrees
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Degrees to radians
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Radians to degrees
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Radians & degreesGet 3 of 4 questions to level up!
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Arc length (from radians)

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Arc length as fraction of circumference
(Opens a modal)
Arc length from subtended angle: radians
(Opens a modal)
Challenge problems: Arc length (radians) 1
(Opens a modal)
Challenge problems: Arc length (radians) 2
(Opens a modal)
Practice
Radians & arc lengthGet 5 of 7 questions to level up!
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Sectors

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Area of a sector
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Area of a sectorGet 3 of 4 questions to level up!
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Quiz 2

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Inscribed angles

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Inscribed angles
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Challenge problems: Inscribed angles
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Inscribed angle theorem proof
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Inscribed angle theorem proof
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Inscribed anglesGet 3 of 4 questions to level up!
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Inscribed shapes problem solving

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Proof: Right triangles inscribed in circles
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Inscribed shapes: find diameter
(Opens a modal)
Inscribed shapes: angle subtended by diameter
(Opens a modal)
Inscribed shapes: find inscribed angle
(Opens a modal)
Challenge problems: Inscribed shapes
(Opens a modal)
Inscribed quadrilaterals proof
(Opens a modal)
Solving inscribed quadrilaterals
(Opens a modal)
Proof: radius is perpendicular to a chord it bisects
(Opens a modal)
Proof: perpendicular radius bisects chord
(Opens a modal)
Area of inscribed equilateral triangle
(Opens a modal)
Practice
Inscribed shapesGet 3 of 4 questions to level up!
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Inscribed quadrilateralsGet 4 of 5 questions to level up!
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Properties of tangents

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Proof: Radius is perpendicular to tangent line
(Opens a modal)
Determining tangent lines: angles
(Opens a modal)
Determining tangent lines: lengths
(Opens a modal)
Proof: Segments tangent to circle from outside point are congruent
(Opens a modal)
Tangents of circles problem (example 1)
(Opens a modal)
Tangents of circles problem (example 2)
(Opens a modal)
Tangents of circles problem (example 3)
(Opens a modal)
Challenge problems: radius & tangent
(Opens a modal)
Challenge problems: circumscribing shapes
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Practice
Tangents of circles problemsGet 3 of 4 questions to level up!
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Quiz 3

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Graphs of circles intro

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Graphing circles from features
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Features of a circle from its graph
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Practice
Graph a circle from its featuresGet 3 of 4 questions to level up!
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Features of a circle from its graphGet 3 of 4 questions to level up!
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Standard equation of a circle

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Features of a circle from its standard equation
(Opens a modal)
Graphing a circle from its standard equation
(Opens a modal)
Writing standard equation of a circle
(Opens a modal)
Practice
Features of a circle from its standard equationGet 3 of 4 questions to level up!
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Graph a circle from its standard equationGet 3 of 4 questions to level up!
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Write standard equation of a circleGet 3 of 4 questions to level up!
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Expanded equation of a circle

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Features of a circle from its expanded equation
(Opens a modal)
Circle equation review
(Opens a modal)
Practice
Features of a circle from its expanded equationGet 3 of 4 questions to level up!
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Graph a circle from its expanded equationGet 3 of 4 questions to level up!
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Quiz 4

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Constructing regular polygons inscribed in circles

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Geometric constructions: circle-inscribed square
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Geometric constructions: circle-inscribed equilateral triangle
(Opens a modal)
Geometric constructions: circle-inscribed regular hexagon
(Opens a modal)

Constructing circumcircles & incircles

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Geometric constructions: triangle-inscribing circle
(Opens a modal)
Geometric constructions: triangle-circumscribing circle
(Opens a modal)

Constructing a line tangent to a circle

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Geometric constructions: circle tangent
(Opens a modal)
Geometric constructions: circle tangent (example 2)
(Opens a modal)
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Unit test

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About this unit

Explore, prove, and apply important properties of circles that have to do with things like arc length, radians, inscribed angles, and tangents.