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Tangent-Radius Property

Angle-Sum Property

Pythagorean Theorem

Centre Point

A tangent is perpendicular (forms right angle) to the radius…

The sum of the 3 angles in a triangle is always 180°

a² + b² = c²

The point at the perfect centre of the circle.

Tangent-Radius Property

A tangent is perpendicular (forms right angle) to the radius…

Angle-Sum Property

The sum of the 3 angles in a triangle is always 180°

Radius

Diameter

Chord

Semi-Circle

Distance from center to any point on circle

Distance across circle through the center

Line segment inside the circle touching two points on the cir…

1/2 of a circle

Radius

Distance from center to any point on circle

Diameter

Distance across circle through the center

Inscribed Angle

Central Angle

Tangent

Chord

An angle formed by two chords in a circle which have a common…

An angle formed by two radii whose vertex is at the centre of…

A line that intersects the circle at one point.

A line segment that joins two points on the circumference of…

Inscribed Angle

An angle formed by two chords in a circle which have a common…

Central Angle

An angle formed by two radii whose vertex is at the centre of…

Tangent-Radius Property

Angle-Sum Property

Pythagorean Theorem

Centre Point

A tangent is perpendicular (forms right angle) to the radius…

The sum of the 3 angles in a triangle is always 180°

a² + b² = c²

The point at the perfect centre of the circle.

Tangent-Radius Property

A tangent is perpendicular (forms right angle) to the radius…

Angle-Sum Property

The sum of the 3 angles in a triangle is always 180°

Tangent-Radius Property

Angle-Sum Property

Pythagorean Theorem

Centre Point

A tangent is perpendicular (forms right angle) to the radius…

The sum of the 3 angles in a triangle is always 180°

a² + b² = c²

The point at the perfect centre of the circle.

Tangent-Radius Property

A tangent is perpendicular (forms right angle) to the radius…

Angle-Sum Property

The sum of the 3 angles in a triangle is always 180°

Diameter

Radius

Chrod

Arc

A line that passes through the centre of the circle and its e…

A line reaching from the centre of the circle to the edge of…

A line segment with both endpoint a on a circle

A portion of the circumference of a circle

Diameter

A line that passes through the centre of the circle and its e…

Radius

A line reaching from the centre of the circle to the edge of…

Radius

Chord

Arc

Central Angle

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

A line that links two points on a circle or curve

A portion of the circumference of a circle

The angle subtended at the center of a circle by two given po…

Radius

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

Chord

A line that links two points on a circle or curve

Tangent line

Point of tangency

Tangent radius property

Chord

Line that intersects a circle at only one point

Where tangent intersects circle

Tangent to circle is perpendicular to radius, creating 90degr…

Line segment that joins 2 points on a circle

Tangent line

Line that intersects a circle at only one point

Point of tangency

Where tangent intersects circle

Tangent-Radius Property

Angle-Sum Property

Pythagorean Theorem

Centre Point

A tangent is perpendicular (forms right angle) to the radius…

The sum of the 3 angles in a triangle is always 180°

a² + b² = c²

The point at the perfect centre of the circle.

Tangent-Radius Property

A tangent is perpendicular (forms right angle) to the radius…

Angle-Sum Property

The sum of the 3 angles in a triangle is always 180°

1.) A tangent and a radius meet at 90…

2.) Two radii form an isosceles triangle

3.)The perpendicular bisector of a cho…

4.) The angle at the center of a circl…

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

Unlike other isosceles triangles they don't have the little t…

A chord is any line drawn across a circle and no matter where…

The angle subtended at the center of a circle is exactly doub…

1.) A tangent and a radius meet at 90…

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

2.) Two radii form an isosceles triangle

Unlike other isosceles triangles they don't have the little t…

circle

center

radius

chord

the set of all points in a plane, equidistant from a given po…

the given point, what the circle is named by

the distance from the center to any point on the circle

a segment whose endpoints are on the circle

circle

the set of all points in a plane, equidistant from a given po…

center

the given point, what the circle is named by

Circle

Center

Radius

Diameter

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

the given point that all points are equidistant from

distance from the center to a point on the circle; segment wh…

distance across the circle, through the center (twice the rad…

Circle

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

Center

the given point that all points are equidistant from

Circle

Center of a circle

Radius

Chord

A line forming a closed loop, every point on which is a fixed…

A point inside the circle. All points on the circle are equid…

the distance from the center of a circle to the edge

a line that connects one point on a circle to another point o…

Circle

A line forming a closed loop, every point on which is a fixed…

Center of a circle

A point inside the circle. All points on the circle are equid…

Chord

Secant

Tangent

Point of Tangency

segment whose endpoints are points on a circle

line that intersects a circle in two points

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

the point where a tangent line and circle intersect

Chord

segment whose endpoints are points on a circle

Secant

line that intersects a circle in two points

Chord

Tangent

Inscribed Angle

Central Angle

A line segment in the circle that intersects two sides of the…

A line that intersects the circle at one point.

An angle whose vertex is on the circle and is half the arc it…

An angle whose vertex is at the center of the circle and is e…

Chord

A line segment in the circle that intersects two sides of the…

Tangent

A line that intersects the circle at one point.

Circle

Radius

Chord

Diameter

Set of all points in a plane that are at a fixed distance fro…

A segment that joins the center of the circle to a point on t…

A line segment that joins two points of a circle

A chord that contains the center of the circle

Circle

Set of all points in a plane that are at a fixed distance fro…

Radius

A segment that joins the center of the circle to a point on t…

Chord

Secant

Tangent

Point of tangency

A segment whose endpoints lie on a circle.

A line that intersects a circle at 2 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 2 points

Circle

Center

Radius

Chord

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

is equal distance from all edges of a circle

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

a segment whose endpoints are on a circle

Circle

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

Center

is equal distance from all edges of a circle

Circle

Center of a Circle

Radius

Chord

The set of all points equidistant from a given point.

The point inside of a circle that is the same distance from e…

A segment with one endpoint on the center of the circle and t…

A segment with both end points on the circumference of the ci…

Circle

The set of all points equidistant from a given point.

Center of a Circle

The point inside of a circle that is the same distance from e…

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

point

line

line segment

protractor

exact location in space

a straight path that extends in both directions forever;... a se…

part of a line having two endpoints

a tool used to draw & measure the size of an angle

point

exact location in space

line

a straight path that extends in both directions forever;... a se…

Circle

Pi (π)

Radius

Radii

A shape consisting of those points in a plane which are equid…

The ratio of the circumference to the diameter of a circle.

A line from the center of the circle of the circle to any poi…

more than 1 radius.

Circle

A shape consisting of those points in a plane which are equid…

Pi (π)

The ratio of the circumference to the diameter of a circle.

Interior/Exterior of a Circle

Chord

Secant

Concentric Circles

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

A chord is a segment whose endpoints lie on a circle

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

Concentric Circles are coplanar circles with the same center

Interior/Exterior of a Circle

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

Chord

A chord is a segment whose endpoints lie on a circle

Interior/Exterior of a Circle

Chord

Secant

Concentric Circles

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

A chord is a segment whose endpoints lie on a circle

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

Concentric Circles are coplanar circles with the same center

Interior/Exterior of a Circle

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

Chord

A chord is a segment whose endpoints lie on a circle

Circle

Radius

Chord

Diameter

The set of all points that are equidistant from a point calle…

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

A segment whose endpoints are on a circle.

A chord that contains the center of the circle.

Circle

The set of all points that are equidistant from a point calle…

Radius

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

Equation of a Circle

Equation of a Circle

- Center of a circle

Radius

(x-h)²+(y-k)²=r², (h, k) is the center, r is the radius.

(x-h)²+(y-k)²=r². ... *h and k are opposite signs, when identify…

(h , k)

The distance from the center of a circle to any point on the…

Equation of a Circle

(x-h)²+(y-k)²=r², (h, k) is the center, r is the radius.

Equation of a Circle

(x-h)²+(y-k)²=r². ... *h and k are opposite signs, when identify…

Central Angle

Inscribed Angle

Cyclic Quadrilateral

Tangent Chord Angle

Central Angle = Intercepted Arc

Inscribed Angle = 1/2 Intercepted Arc

Opposite angles in a cyclic quadrilateral are supplementary.

Tangent Chord Angle = 1/2 Intercepted Arc

Central Angle

Central Angle = Intercepted Arc

Inscribed Angle

Inscribed Angle = 1/2 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

Diameter

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

The distance from the center of a circle to any point on the…

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

A chord that passes through the center of the circle

Circle

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

Radius

The distance from the center of a circle to any point on the…

circle

radius

diameter

chord

a set of all points that are equidistant from the center of t…

a segment who's endpoints are the center of the circle and an…

a chord that passes through the center of the circle

a segment who's endpoints are on the circle

circle

a set of all points that are equidistant from the center of t…

radius

a segment who's endpoints are the center of the circle and an…

chord

circumference

diameter

radius

a line segment passing through a circle that has its endpoint…

the distance around a circle

a chord passing through the center of a circle

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

chord

a line segment passing through a circle that has its endpoint…

circumference

the distance around a circle

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…

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

arc

endpoints

minor arc

major arc

a curved line along the circumference of a circle

the points where an arc ends

an arc that takes up less than half a circle

an arc that takes up more than half of a circle, ( must be la…

arc

a curved line along the circumference of a circle

endpoints

the points where an arc ends

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…

Two Tangent Theorem

Chord-Chord Angle

Secant-Tangent Angle OR Tangent-Tangen…

Area of a sector

If 2 tangent segments are drawn to a circle from an external…

The measure of a chord-chord angle equals half the sum of the…

The measure of an angle whose vertex is OUTSIDE a circle is h…

Two Tangent Theorem

If 2 tangent segments are drawn to a circle from an external…

Chord-Chord Angle

The measure of a chord-chord angle equals half the sum of the…

circumscribed angle

intercepted arc

center of a circle

adjacent arcs

An angle whose sides are tangent to a circle.

An arc that lies between two lines, rays, or segments.

The point from which all points on a circle are equidistant.

Arcs of a circle that have exactly one point in common.

circumscribed angle

An angle whose sides are tangent to a circle.

intercepted arc

An arc that lies between two lines, rays, or segments.

Arc Length

Sector Area

Right-angle corollary

Arc-intercept corollary

measure of arc/360 x 2πr

measure of arc/360 x πr²

if an inscribed angle intercepts a semicircle, then the angle…

if two inscribed angles intercept the same arc, then they hav…

Arc Length

measure of arc/360 x 2πr

Sector Area

measure of arc/360 x πr²

Radius

Chord

Secant

Diameter

any segment that joins the center of the circle to any point…

a segment whose endpoints lie on a circle

a line that contains a chord

is a chord that contains the center of the circle (twice the…

Radius

any segment that joins the center of the circle to any point…

Chord

a segment whose endpoints lie on a circle

Inscribed Angle

Central Angle

Equal Inscribed Angles

Subtended

An angle formed by to chords that share an endpoint. This is…

An angle formed by two radii of a circle. This is twice the m…

Inscribed angles are equal if they are subtended by the same…

Lying opposite to something. If the arc is AB, then the angle…

Inscribed Angle

An angle formed by to chords that share an endpoint. This is…

Central Angle

An angle formed by two radii of a circle. This is twice the m…

Degree

Tangent

Inscribed angle

Central angle

Unit of measure that measures an angle within a shape

A straight line or plane that touches a curve of s circle

Angle created when line segments (not radii) create an angle…

Angle created by the arms (radii) of the circle

Degree

Unit of measure that measures an angle within a shape

Tangent

A straight line or plane that touches a curve of s circle

Circle

Radius

Diameter

Chord

A set of points in a plane that are equidistant from a fixed…

Segment in a circle that starts at the center and ends at a p…

Segment in a circle that starts at a point on the circle, pas…

Segment in a circle that starts at a point on the circle and…

Circle

A set of points in a plane that are equidistant from a fixed…

Radius

Segment in a circle that starts at the center and ends at a p…

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…