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Chord

Diameter

Secant of a circle

Tangent to a circle

A segment whose endpoints are on the circle

Distance across the circle through its center

Intersects The Circle at exactly two points

A line that intersects a circle at exactly one point

Chord

A segment whose endpoints are on the circle

Diameter

Distance across the circle through its center

Radius

Diameter

Tangent

Chord

A line drawn from the centre of the circle to a point on the…

A line joining two points on the circumference of the circle…

A line drawn from a point outside the circle which touches th…

A line joining two points on the circumference of the circle…

Radius

A line drawn from the centre of the circle to a point on the…

Diameter

A line joining two points on the circumference of the circle…

circle

interior

exterior

chord

all possible points in a plane equidistant from a given point…

set of all points inside of a circle

set of all points outside a circle

a line segement with end points on the circle

circle

all possible points in a plane equidistant from a given point…

interior

set of all points inside of a circle

Chord

Central angles

Inscribed angle

Arc

A line segment that joins 2 points on a circle.... It doesn't go…

These angles have their vertec at the center if the circle. T…

Angle formed by 2 chords which meet at the same endpoint

The circumfrence of a circle between the inscribed angles

Chord

A line segment that joins 2 points on a circle.... It doesn't go…

Central angles

These angles have their vertec at the center if the circle. T…

Diameter

Radius

Chord

Tangent

A line segment that connects two points on the edge of the ci…

A line segment that connects the centre pt to the edge of the…

A line segment that connects two points on the edge of the ci…

A line that touches the circle at one point

Diameter

A line segment that connects two points on the edge of the ci…

Radius

A line segment that connects the centre pt to the edge of the…

chord

radius

diameter

circumference

a line segment joining two points on the circumference of a c…

a line segment joining the centre of a circle to the outside…

the distance across a circle through its centre. represented…

the boundary of a distance around a circle. this is a linear…

chord

a line segment joining two points on the circumference of a c…

radius

a line segment joining the centre of a circle to the outside…

central angle

arc of a central angle

Total of all central angles

inscribed angle

An angle whose vertex is the center of the circle... Arc = Angle…

Equals the angle

equals 360 degrees

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

central angle

An angle whose vertex is the center of the circle... Arc = Angle…

arc of a central angle

Equals the angle

Circle

Radius

Radii

Chord

Shape consisting of those points in a plane which have EQUIDI…

A line from the center of the circle to any point on the circle

more than on radius

A line segment that links two points on a circle

Circle

Shape consisting of those points in a plane which have EQUIDI…

Radius

A line from the center of the circle to any point on the circle

Tangent

Secant

Chord

Rotation

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

A line that intersects a circle in two points.

A segment whose end points are points on a circle.

A transformation in which a figure is turned about a fixed po…

Tangent

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

Secant

A line that intersects a circle in two points.

concentric circles

congruent circles

major arc

minor arc

have the same center; different diameters

have the same diameter; different center

longer than a semicircle; named by 3 letters

shorter than a semicircle; named by 2 letters

concentric circles

have the same center; different diameters

congruent circles

have the same diameter; different center

Circle

Center

Radius

Circumfrence

a 2D figure formed by a line that forms a closed loop, whose…

the fixed point inside the circle; all points on circle are e…

distance from circle center to any point on the circle

distance around circle, circle's perimeter, P = d x π

Circle

a 2D figure formed by a line that forms a closed loop, whose…

Center

the fixed point inside the circle; all points on circle are e…

chord

bisect

angle

central angle

A segment whose endpoints lie on a circle

to divide into two equal parts

A figure formed by two rays with a common endpoint

an angle whose vertex is the center of the circle

chord

A segment whose endpoints lie on a circle

bisect

to divide into two equal parts

circle

radius

diameter

chord

set of points equidistant from a given point

a segment from the center of the circle

a segment through the center; divides the circle in half

a segment that touches two points on the circle

circle

set of points equidistant from a given point

radius

a segment from the center of the circle

chord

central angle

minor arc

sector

straight segments joining 2 points on any circle

angle whose vertex lays on the center, legs are radii, with a…

in between points A and B of the central angle shorter or equ…

portion enclosed by two radii and an arc (central angle)

chord

straight segments joining 2 points on any circle

central angle

angle whose vertex lays on the center, legs are radii, with a…

Intercepted Arc

Radius

Chord

Inscribed Angle

The arc formed using the endpoints of a chord

A segment from the center of the circle to any point on the c…

A segment whose endpoints lie on a circle

An angle whose vertex lies on a circle and whose sides contai…

Intercepted Arc

The arc formed using the endpoints of a chord

Radius

A segment from the center of the circle to any point on the c…

circle

center

radius

chord

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

the point from which all points of the circle are equidistant

a line segment from the center of the circle to any point on…

a line segment whose endpoints are points of the circle

circle

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

center

the point from which all points of the circle are equidistant

Circle

Radius

Chord

Diameter

a plane shape bounded by a continuous line... which is always th…

the distance from the centre of a circle to its circumference.

straight line joining two points on... the circumference of a ci…

a straight line passing through the centre of a circle... to tou…

Circle

a plane shape bounded by a continuous line... which is always th…

Radius

the distance from the centre of a circle to its circumference.

Circle

Special Segments in a Circle

Radius Formula

Diameter Formula

the locus or set of all points in a plane equidistant from a…

Radius - is a segment with endpoints at the center and on the…

r=d/2 OR r=.5(d)

d=2r

Circle

the locus or set of all points in a plane equidistant from a…

Special Segments in a Circle

Radius - is a segment with endpoints at the center and on the…

Circle

Arc

Minor Arc

Major Arc

the set of all points on a plane at a set distance from a giv…

two points on a circle and the continuous (unbroken) part of…

An arc whose length is less than half of the circle. Named wi…

An arc of a circle whose length is more than half of the circ…

Circle

the set of all points on a plane at a set distance from a giv…

Arc

two points on a circle and the continuous (unbroken) part of…

circle

radius

chord

diameter

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

segment with one end point on the circle and one end point at…

segment that joins two points on the circle ... (segment with e…

a chord that goes through the center and is the longest chord…

circle

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

radius

segment with one end point on the circle and one end point at…

What is a tangent?

What angle does a tangent and a radius…

What do two radii (radius) form?

What is a chord?

A tangent is a line that just touches a single point on the c…

90 degrees

An isosceles triangle.

Any line drawn across a circle.

What is a tangent?

A tangent is a line that just touches a single point on the c…

What angle does a tangent and a radius…

90 degrees

Find the measure of Central Angle

Find the measure of an Inscribed Angle.

Find the measure of an Angle INSIDE th…

Find the measure of an Angle OUTSIDE t…

It is equal to its Intercepted arc.

It is equal to 1/2 of its Intercepted arc.

It is equal to 1/2 of the sum of the arcs.

It is equal to 1/2 DIFFERENCE of the arcs

Find the measure of Central Angle

It is equal to its Intercepted arc.

Find the measure of an Inscribed Angle.

It is equal to 1/2 of its Intercepted arc.

circle

radius

diameter

central angle

The set of all points in a plane that are the same distance f…

a segment that connects the center of a circle to the circle

a segment that passes through the center of a circle and has…

an angle with its vertex at the center of a circle

circle

The set of all points in a plane that are the same distance f…

radius

a segment that connects the center of a circle to the circle

Circle

Radius

Chord

Secant

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

A segment whose endpoints are the center of a circle and... a po…

A segment whose endpoints are 2 points... on a circle.

A line that intersects a circle in two points

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... a po…

definition of a circle

sphere

secant

tangent

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

set of all points that are equidistant from a given point/its…

line which intersects the circle at 2 distinct points

line which intersects a circle at exactly one point

definition of a circle

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

sphere

set of all points that are equidistant from a given point/its…

Circle

Center

Radius

Diameter

The locus of all points in a plane equidistant from a given p…

The central point where radii form a locus of points called a…

Any segment with endpoints that are the center of the circle…

A chord that passes through the center of the circle

Circle

The locus of all points in a plane equidistant from a given p…

Center

The central point where radii form a locus of points called a…

Center

Chord

Secant

Point of Tangency

given point from which all points on a circle are the same di…

A segment whose endpoints are 2 points... on a circle.

A line that intersects a circle in two points

Point where a Tangent segment touches a circle

Center

given point from which all points on a circle are the same di…

Chord

A segment whose endpoints are 2 points... on a circle.

symmetry

sector

arc

chord

splits through the center evenly (same on each side)

fractional piece of the circles area

fractional piece of the circles circumference

segment with both end points on the circle

symmetry

splits through the center evenly (same on each side)

sector

fractional piece of the circles area

Circle

Chord

Tangent

Secant

a set of points equidistant from a center point in a plane ... *…

a segment joining two points on the circle

a line that intersects a circle at only one point

a line that intersects a circle at two points

Circle

a set of points equidistant from a center point in a plane ... *…

Chord

a segment joining two points on the circle

Radius

Diameter

Chord

circumference

Any straight line from the center of a circle to its circumfe…

the distance measured from one point on a circle to another g…

Any straight line linking two points on a circle`s circumfere…

The total length of the outside edge (perimeter) of a circle.

Radius

Any straight line from the center of a circle to its circumfe…

Diameter

the distance measured from one point on a circle to another g…

Theorem 10.1

Theorem 10.3

Theorem 10.4

Theorem 10.5

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

If two segments from the same exterior point are tangent to a…

In the same circle, or in congruent circles, two minor arcs a…

If a diameter is perpendicular to a chord, then the diameter…

Theorem 10.1

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

Theorem 10.3

If two segments from the same exterior point are tangent to a…

circle

chord

radius

diameter

the set of points in a plane that are fixed distance from a g…

a segment whose endpoints both lie on the same circle

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

a segment whose endpoints are the circle and passes through t…

circle

the set of points in a plane that are fixed distance from a g…

chord

a segment whose endpoints both lie on the same circle

In a plane, a line is tangent to a cir…

Tangent segments from a common externa…

minor arc

major arc

If and only if the line is perpendicular to a radius of the c…

congruent

part of circle less than 180

part of circle measures between 180 - 360

In a plane, a line is tangent to a cir…

If and only if the line is perpendicular to a radius of the c…

Tangent segments from a common externa…

congruent

circle

radius

diameter

chord

The set of all points in a plane that are the same distance f…

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

A straight line passing from side to side through the center…

A straight line connecting two points on a circle... can neve…

circle

The set of all points in a plane that are the same distance f…

radius

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

Radius

Diameter

Chord

Secant Line

Half the diameter of a circle

The width of the circle that goes from one side of a circle t…

A segment where the endpoints are on one circle

Line in as circle that goes on forever. Intersects the circle…

Radius

Half the diameter of a circle

Diameter

The width of the circle that goes from one side of a circle t…

center

chord

secant

tangent line

equidistant from the circumference

segment end point to end point on the circle

goes all the way through the circle

intersects once on the edge... -perpendicular to the radius

center

equidistant from the circumference

chord

segment end point to end point on the circle

Circle

Radius

Chord

Diameter

The set of all points in a plane at a given distance from a g…

Any segment joining the center of the circle to a point of th…

A segment whose endpoints lie on a circle.

A chord that contains the center of the circle. 2 times the r…

Circle

The set of all points in a plane at a given distance from a g…

Radius

Any segment joining the center of the circle to a point of th…

Circle

Radius

Chord

Diameter

The set of all points equidistant from a given point called t…

A segment that with one endpoint on the circle, and the other…

A segment whose endpoints lie on a circle

A chord that passes through the center of the circle.

Circle

The set of all points equidistant from a given point called t…

Radius

A segment that with one endpoint on the circle, and the other…

chord bisector thm

equidistant thm

congruent tangents thm

tangent segments

if a diameter is ⟂ to a chord, then the diameter bisects the…

two congruent chords are the same distance from the center of…

the tangent segments to a circle from a point outside the cir…

a part of the tangent line with one endpoint outside the circ…

chord bisector thm

if a diameter is ⟂ to a chord, then the diameter bisects the…

equidistant thm

two congruent chords are the same distance from the center of…

circle

chord

secant

tangent

a locus of points that are equidistant point called the radius

a segment whose endpoints lie on the circle

a line that intersects a circle at 2 points

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

circle

a locus of points that are equidistant point called the radius

chord

a segment whose endpoints lie on the circle

concentric circle

major arc

minor arc

arc

circles that have a common center

more than 1/2 way around the outside of a circle

less than 1/2 way around the outside of a circle

piece or portion of the circumference

concentric circle

circles that have a common center

major arc

more than 1/2 way around the outside of a circle