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12.1 interior of a circle

12.1 exterior of a circle

12.1 chord

12.1 secant

the set of all points inside the circle

the set of all points outside the circle

a segment whose endpoints lie on a circle

a line that intersects a circle at two points

12.1 interior of a circle

the set of all points inside the circle

12.1 exterior of a circle

the set of all points outside the circle

Circle

center

radius

Diameter

A round plane figure whose boundary consists of points equidi…

The point at the middle of the circle

A straight line segment that reaches from the center of the s…

A straight line segment passing through the center of a shape…

Circle

A round plane figure whose boundary consists of points equidi…

center

The point at the middle of the circle

If a line is tangent to a circle, then

If a line in the plane of a circle is…

If 2 tangent segments to a circle shar…

Within a circle or in congruent circle…

The line is perpendicular to the radius at the point of tange…

The line is a tangent to the circle.

The 2 segments are congruent.

Congruent arcs.

If a line is tangent to a circle, then

The line is perpendicular to the radius at the point of tange…

If a line in the plane of a circle is…

The line is a tangent to the circle.

Tangent

Theorem 12-1

Theorem 12-3

Chords

A line that hits a circle only at one point

If a line is tangent to the circle, then it is perpendicular…

If two tangent segments share a common endpoint, then they ar…

A segment whose endpoints are on a circle

Tangent

A line that hits a circle only at one point

Theorem 12-1

If a line is tangent to the circle, then it is perpendicular…

If a line is tangent to a circle, then

If a line in the plane of a circle is…

If 2 tangent segments to a circle shar…

Within a circle or in congruent circle…

The line is perpendicular to the radius at the point of tange…

The line is a tangent to the circle.

The 2 segments are congruent.

Congruent arcs.

If a line is tangent to a circle, then

The line is perpendicular to the radius at the point of tange…

If a line in the plane of a circle is…

The line is a tangent to the circle.

a circle

A radius

all radi of the same cirlce

a chord of a circle

is the set of all points in a plane that are at a given dista…

is a line segment that joins the center of the circle to a po…

are congruent

is a line segment that joints two points of the circle

a circle

is the set of all points in a plane that are at a given dista…

A radius

is a line segment that joins the center of the circle to a po…

Tangent line

If two tangent segments to a circle sh…

Within a circle or in congruent circle…

Within a circle or in congruent circle…

Perpendicular to the radius at the point of tangency

Congruent

Congruent arcs

Chords

Tangent line

Perpendicular to the radius at the point of tangency

If two tangent segments to a circle sh…

Congruent

tangent

point of tangency

If a line is tangent to a circle...

If a line in the plane of a circle is…

a line in the plane of the circle that intersects the circle…

the point where a circle and a tangent intersect

Then the line is perpendicular to the radius at the point of…

Then the line is tangent to the circle

tangent

a line in the plane of the circle that intersects the circle…

point of tangency

the point where a circle and a tangent intersect

Chord

Secant

Tangent of a Circle

Point of a Tangency

A segment whose endpoints lie on a circle

A line that intersects a circle at two points

A line in the same plane as a circle that intersects it at ex…

The point where the tangent and a circle intersect

Chord

A segment whose endpoints lie on a circle

Secant

A line that intersects a circle at two points

arc

arc length

central angle of a circle

chord

an unbroken part of a circle consisting of two points on the…

the distance along an arc measured in linear units

an angle whose vertex is the center of a circle

a segment whose endpoints lie on a circle

arc

an unbroken part of a circle consisting of two points on the…

arc length

the distance along an arc measured in linear units

12.1 interior of a circle

12.1 exterior of a circle

12.1 chord

12.1 secant

the set of all points inside the circle

the set of all points outside the circle

a segment whose endpoints lie on a circle

a line that intersects a circle at two points

12.1 interior of a circle

the set of all points inside the circle

12.1 exterior of a circle

the set of all points outside the circle

circle

Center of a circle

Interior of a circle

Exterior of a circle

the set of all points in a plane that are equidistant from a…

The point that the distance is equidistant from

set of all points inside circle

set of all points outside the circle

circle

the set of all points in a plane that are equidistant from a…

Center of a circle

The point that the distance is equidistant from

Tangent line

Point of tangency

Perpendicular, radius

(n-2)180

a line in the plane of the circle that intersects the circle…

the point where a circle and a tangent intersect

A tangent is ______ to the ______ of the circle at the point…

Sum of angle measure formula

Tangent line

a line in the plane of the circle that intersects the circle…

Point of tangency

the point where a circle and a tangent intersect

tangent line

tangent circle

exterior

interior

a line that intersects a circle in exactly one point, called…

circles that intersect in one point

all points of plane that are outside of circle

all points of the plane that are inside circle

tangent line

a line that intersects a circle in exactly one point, called…

tangent circle

circles that intersect in one point

Circle

Radius

Congruent Circles

Concentric Circles

Set of all points in a plane equidistant from a given point k…

Segment whose endpoints are the center and a point on the cir…

Circles with congruent radius.

Coplanar circles with the same center.

Circle

Set of all points in a plane equidistant from a given point k…

Radius

Segment whose endpoints are the center and a point on the cir…

chord

diameter

radius

secant

A segment whose endpoints lie on a circle

A chord that passes through the center of the circle

A straight line from the center to the circumference of a cir…

A line that intersects a circle in two points

chord

A segment whose endpoints lie on a circle

diameter

A chord that passes through the center of the circle

Inscribed Angle

Intercepted Arc

Subtend

Secant Segment

An angle whose vertex is on a circle and whose sides contain…

Endpoints that lie on the sides of an inscribed angle and all…

A chord or arc subtends an angle if its endpoints lie on the…

a segment of a secant with at least one endpoint on the circle.

Inscribed Angle

An angle whose vertex is on a circle and whose sides contain…

Intercepted Arc

Endpoints that lie on the sides of an inscribed angle and all…

circle

point

congruent

chord

A ____ is the set of all points in a plane that are at a give…

A radius is a line segment that joins the center of the circl…

All radii of the same circle are ____ .

A ____ of a circle is a line segment that joins two points of…

circle

A ____ is the set of all points in a plane that are at a give…

point

A radius is a line segment that joins the center of the circl…

diameter

radius(radii)

secant

chord

a chord of a circle that goes through the center.

half a diameter, a segment from center of a circle with other…

is a line that intersects a circle at two points.

is a segment whose endpoints is on a circle

diameter

a chord of a circle that goes through the center.

radius(radii)

half a diameter, a segment from center of a circle with other…

Circle

Concentric

Chord

Diameter

A circle is the set of all points in a plane that are at a gi…

Circles are concentric iff they lie in the same plane and hav…

A chord of a circle is a line segment that joins two points o…

The diameter of a circle is a chord that contains the center

Circle

A circle is the set of all points in a plane that are at a gi…

Concentric

Circles are concentric iff they lie in the same plane and hav…

Circle

Radius

Radii

Chord

set of all points in a plane that are at a given distance fro…

a line segment that joins the center of the circle to a point…

all radii of the same circle are congruent

a line segment that joins 2 points of the circle

Circle

set of all points in a plane that are at a given distance fro…

Radius

a line segment that joins the center of the circle to a point…

Tangent Line

Two tangent segments

Chord

Congruent circles

The straight line that just touches the circle. It is perpend…

If two tangent segments to a circle share a common endpoint o…

A segment whose endpoints are on a circle

Within a circle or in congruent circles, congruent central an…

Tangent Line

The straight line that just touches the circle. It is perpend…

Two tangent segments

If two tangent segments to a circle share a common endpoint o…

secant

chord

tangent

interior

a secant is a line that intersects a circle at two points.

a chord is a segment whose endpoints lie on a circle

a tangent is a line in the same plane as the circle that inte…

the interior of a circle is the set of all points inside the…

secant

a secant is a line that intersects a circle at two points.

chord

a chord is a segment whose endpoints lie on a circle

a circle

interior of a circle

exterior of a circle

chord

the set of all points in a plane that are equidistant from a…

the set of all points inside the circle

the set of all points outside the circle

a segment whose endpoints lie on a circle

a circle

the set of all points in a plane that are equidistant from a…

interior of a circle

the set of all points inside the circle

diameter

radius

secant

chord

a chord of a circle that goes through the center

half a diameter a segment from center of a circle with other…

is a line that intersects a circle at two points

is a segment whose endpoints lie on a circle

diameter

a chord of a circle that goes through the center

radius

half a diameter a segment from center of a circle with other…

circle

center

radius

chord

Set of all points in a plane that are equidistant from a give…

a point in the middle of the circle making everything equidis…

A segments whose endpoints are the center and anywhere else o…

A segment whose endpoints are on a circle.

circle

Set of all points in a plane that are equidistant from a give…

center

a point in the middle of the circle making everything equidis…

Diameter

Radius(radii)

Secant

Chord

A chord of a circle that goes through the center.

Half of diameter a segment from center of a circle with other…

A line that intersects a circle at two points.

A segment whose endpoints lie on a circle.

Diameter

A chord of a circle that goes through the center.

Radius(radii)

Half of diameter a segment from center of a circle with other…

Secant

Chord

Tangent

Interior

Line that intersects a circle at two points

Segment whose endpoints lie on a circle.

A line in the same plane as the circle that intersects it at…

The set of all points inside the circle.

Secant

Line that intersects a circle at two points

Chord

Segment whose endpoints lie on a circle.

interior of a circle

chord

secant

tangent

set of all points inside the circle

whose endpoints lie on a circle

line that intersects the circle at two points

is a line in the same plane as a circle that intersects it at…

interior of a circle

set of all points inside the circle

chord

whose endpoints lie on a circle

circle

chord

diameter

radius

the set of all points in a plane that are equidistant from a…

a segment whose endpoints are on the circle.

a chord that passes through a center and the other endpoints…

a segment where one endpoint is at the center and the other e…

circle

the set of all points in a plane that are equidistant from a…

chord

a segment whose endpoints are on the circle.

Circle

Tangent Circles

Radius

Chord

The set of all points in a plane that are equidistant from a…

Coplanar circles that intersect in one point.

A segment whose endpoints are the center and any point on the…

A segment whose endpoints are on a circle.

Circle

The set of all points in a plane that are equidistant from a…

Tangent Circles

Coplanar circles that intersect in one point.

chord

inscribed angle

intercepted arc

locus

a segment whose endpoints are on the circle

an angle is inscribed in a circle if the vertex of the angle…

an arc of a circle having endpoints on the sides of an inscri…

a set of points, all of which meet a stated condition

chord

a segment whose endpoints are on the circle

inscribed angle

an angle is inscribed in a circle if the vertex of the angle…

Tangent

Theorem 12-1

Theorem 12-2

Theorem 12-3

A line which touches a circle or ellipse at just one point is…

If a line is tangent to a circle, then the line is perpendicu…

If a line in the plane of a circle is perpendicular to a radi…

If two tangent segments to a circle share a common endpoint o…

Tangent

A line which touches a circle or ellipse at just one point is…

Theorem 12-1

If a line is tangent to a circle, then the line is perpendicu…

Chord

Secant

Tangent

Point of tangency

A segment of the circle whose endpoints lie on the circle.

A line that intersects the circle at two points.

Is a line that is in the same plane as a circle and intersect…

The point where the tangent and circle intersect.

Chord

A segment of the circle whose endpoints lie on the circle.

Secant

A line that intersects the circle at two points.

Radius

Chord

Diameter

Central angle

segment that has one endpoint at center, and on on circle

segment with endpoints on circle

special chord that goes thru center (double radius)

∠ whose vertex is center of circle, sum of the measures of ce…

Radius

segment that has one endpoint at center, and on on circle

Chord

segment with endpoints on circle

Circle

Radius

Corollary to Definition of A Circle

Concentric Circles

The set of all points in a plane that are a given distance fr…

A radius of a circle is a line segment that connects the cent…

All radii of a circle are equal

Circles are concentric iff they lie in the same plane and hav…

Circle

The set of all points in a plane that are a given distance fr…

Radius

A radius of a circle is a line segment that connects the cent…

center

concentric circles

chord

radius

The point in the interior of a circle that is equal distance…

Circles that lie in the same plane and have the same center

A line segment with both endpoints on the circle.

A line segment with one endpoint at the center of a circle an…

center

The point in the interior of a circle that is equal distance…

concentric circles

Circles that lie in the same plane and have the same center

chord

secant

a circle is named by its___________

tangent

a segment whose end pts are on the circle

a line that contains a chord

center

a line intersects one point on a circle. ... that point is calle…

chord

a segment whose end pts are on the circle

secant

a line that contains a chord

chord

diameter

radius

secant

A segment whose endpoints lie on a circle

A chord that passes through the center of the circle

A straight line from the center to the circumference of a cir…

A line that intersects a circle in two points

chord

A segment whose endpoints lie on a circle

diameter

A chord that passes through the center of the circle

circle

radius

chord

diameter

the set of all points in a plane that are equidistant from a…

a segment whose endpoints are the center of a circle and any…

a segment whose endpoints are on a circle

a chord that contains the center of the circle

circle

the set of all points in a plane that are equidistant from a…

radius

a segment whose endpoints are the center of a circle and any…

Chord

Tangent

Secant

Inscribed Angle

A segment whose two endpoints are on the circle.

A line that contains exactly one point of a circle.

A line that contains two points of a circle.

An angle whose vertex is on the center of a circle and its si…

Chord

A segment whose two endpoints are on the circle.

Tangent

A line that contains exactly one point of a circle.

Chord

Diameter

Arc

Central Angle

a segment whose endpoints are on the circle

a chord that contains the center of the circle

two points on a circle and all of the points on the circle ne…

an angle whose vertex is the center of the circle

Chord

a segment whose endpoints are on the circle

Diameter

a chord that contains the center of the circle

Chord

Diameter

Arc

Central Angle

a segment whose endpoints are on the circle

a chord that contains the center of the circle

two points on a circle and all of the points on the circle ne…

an angle whose vertex is the center of the circle

Chord

a segment whose endpoints are on the circle

Diameter

a chord that contains the center of the circle