Circles

Circle basics

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Circles glossary

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Radius, diameter, circumference & π

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Proof: all circles are similar

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Arc measure

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Finding arc measures with equations

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Arc measureGet 3 of 4 questions to level up!

Arc measure with equationsGet 3 of 4 questions to level up!

Arc length (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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Arc lengthGet 3 of 4 questions to level up!

Introduction to radians

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Radians & degreesGet 3 of 4 questions to level up!

Arc length (radians)

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Arc length as fraction of circumference

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Arc length from subtended angle: radians

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Challenge problems: Arc length (radians) 1

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Challenge problems: Arc length (radians) 2

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Radians & arc lengthGet 5 of 7 questions to level up!

Sectors

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Area of a sector

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Area of a sectorGet 3 of 4 questions to level up!

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!

Inscribed shapes problem solving

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Proof: Right triangles inscribed in circles

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Inscribed shapes: find diameter

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Inscribed shapes: angle subtended by diameter

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Inscribed shapes: find inscribed angle

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Challenge problems: Inscribed shapes

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Inscribed quadrilaterals proof

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Solving inscribed quadrilaterals

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Proof: radius is perpendicular to a chord it bisects

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Proof: perpendicular radius bisects chord

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Area of inscribed equilateral triangle

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Practice

Inscribed shapesGet 3 of 4 questions to level up!

Inscribed quadrilateralsGet 4 of 5 questions to level up!

Properties of tangents

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Proof: Radius is perpendicular to tangent line

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Determining tangent lines: angles

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Determining tangent lines: lengths

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Proof: Segments tangent to circle from outside point are congruent

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Tangents of circles problem (example 1)

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Tangents of circles problem (example 2)

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Tangents of circles problem (example 3)

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Challenge problems: radius & tangent

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Challenge problems: circumscribing shapes

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Tangents of circles problemsGet 3 of 4 questions to level up!

Standard equation of a circle

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Features of a circle from its standard equation

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Graphing a circle from its standard equation

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Writing standard equation of a circle

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Features of a circle from its standard equationGet 3 of 4 questions to level up!

Graph a circle from its standard equationGet 3 of 4 questions to level up!

Write standard equation of a circleGet 3 of 4 questions to level up!

Expanded equation of a circle

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Features of a circle from its expanded equation

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Circle equation review

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Features of a circle from its expanded equationGet 3 of 4 questions to level up!

Graph a circle from its expanded equationGet 3 of 4 questions to level up!

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

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Geometric constructions: circle-inscribed regular hexagon

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Constructing circumcircles & incircles

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Geometric constructions: triangle-inscribing circle

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Geometric constructions: triangle-circumscribing circle

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Constructing a line tangent to a circle

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Geometric constructions: circle tangent

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Geometric constructions: circle tangent (example 2)

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