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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…

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…

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…

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…

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

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

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

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

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.

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…

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

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

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…

Circle

Center

Radius

Diameter

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 of the circle to any point on th…

The distance across the circle passing through its center.

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

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

Secant

Tangent

Point of tangency

A locus of points equidistant from a fixed point

A line that intersects a circle at exactly 2 points

A line that intersects a circle at exactly 1 point

The point at which the tangent line intersects the circle

Circle

A locus of points equidistant from a fixed point

Secant

A line that intersects a circle at exactly 2 points

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…

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…

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

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°

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.

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…

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…

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…

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

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…

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

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

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

Polygon

Circumference

Circle

Radius

A shape with all sides and angles equal.

The distance around the edge of a circle.

A shape with all points the same distance from its centre.

The distance from the centre of a circle to any point of the…

Polygon

A shape with all sides and angles equal.

Circumference

The distance around the edge of a circle.

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