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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°

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°

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°

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

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

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…

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

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…

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…

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…

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…

Chord

Central Angle

Inscribed Angle

Arc

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

an angle formed by two radii of the circle. the vertex of the…

an angle formed by two chords that share a common endpoint. t…

a portion of the circumference of a circle. a minor arc is le…

Chord

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

Central Angle

an angle formed by two radii of the circle. the vertex of the…

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

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…

right triangle

isocelese triangle

equilateral triangle

scalene triangle

one 90 degree angle

two equal sides, two base angles are equal

sides are all the same, All angles are 60 degrees

no equal sides

right triangle

one 90 degree angle

isocelese triangle

two equal sides, two base angles are equal

radius

diameter

circumference

area of circle

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

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

The distance around a circle

A=πr²

radius

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

diameter

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

tangent

point of tangency

tangent-radius property

perpendicular to chord property #1

line that intersects a circle at only one point

point where the tangent intersects the circle

a tangent that is perpendicular to the radius at the point of…

where, from the centre of a circle to a chord bisects the cho…

tangent

line that intersects a circle at only one point

point of tangency

point where the tangent intersects the circle

circle

center

radius

chord

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

the point in the middle of the circle - equal distance from t…

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

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

circle

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

center

the point in the middle of the circle - equal distance from t…

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.

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

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

Radius

Diameter

Tangent

Point of Tangency

The distance or line segment from the centre of a circle to a…

The distance across a circle, measured through its centre; th…

A line that intersects a circle at only one point.

The point where a tangent intersects (touches) the circle.

Radius

The distance or line segment from the centre of a circle to a…

Diameter

The distance across a circle, measured through its centre; th…

Circumference

Center

Diameter

Radius

The distance around a circle is its

every point on a circle is the same distance from its

the distance across a circle though it's center is its

the distance from a circle to it's center is its

Circumference

The distance around a circle is its

Center

every point on a circle is the same distance from its

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

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

Sector

Tangent

Chord

An arc

A wedge shaped area, cut right from the center

A straight line that touches the outside of a circle

A line across the inside of the circle

Part of the circumference of the circle

Sector

A wedge shaped area, cut right from the center

Tangent

A straight line that touches the outside of a circle

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…

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.

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.

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