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Alternate Interior Angles

Consecutive Interior Angles

Alternate Exterior Angles

Corresponding Angles

Located on the interior of the lines, on opposite sides of th…

Located on the interior of the lines, on the same side of the…

Located on the exterior of the lines, on opposite sides of th…

Located on the interior and exterior of the lines, on the sam…

Alternate Interior Angles

Located on the interior of the lines, on opposite sides of th…

Consecutive Interior Angles

Located on the interior of the lines, on the same side of the…

radius (regular polygon)

polygon

remote interior angles

linear scale factor

a line segment that connects the center of a regular polygon…

a two-dimensional closed figure of three or more line segment…

when a triangle has an exterior angles, these angles are the…

the ratio of similarity. the ratio of any pair of correspondi…

radius (regular polygon)

a line segment that connects the center of a regular polygon…

polygon

a two-dimensional closed figure of three or more line segment…

Obtuse

Acute

Right Angle

Point

An angle that measures more than 90 degrees.

An angle that measures less than 90 degrees.

An angle that measures 90 degrees.

A place in space that is often marked by a letter or number.

Obtuse

An angle that measures more than 90 degrees.

Acute

An angle that measures less than 90 degrees.

Vertical Angles

Angle Addition Postulate

Linear Pairs

Consecutive Adjacent Angles

vertical angles are equal in measure

If C is a point in the interior of ∠AOB, then m∠AOC + m∠COB =…

Two angles that form a linear pair are supplementary (=180⁰)

Consecutive adjacent angles on a line sum to 180⁰

Vertical Angles

vertical angles are equal in measure

Angle Addition Postulate

If C is a point in the interior of ∠AOB, then m∠AOC + m∠COB =…

Line

Collinear points

Coplanar

Segment

A straight, unbroken set of points that goes on forever. It h…

A set of points that lie on the same line

Points, lines, or segments that lie on the same plane

A part of a line with two endpoints.

Line

A straight, unbroken set of points that goes on forever. It h…

Collinear points

A set of points that lie on the same line

Line

Collinear points

Coplanar

Segment

A straight, unbroken set of points that goes on forever. It h…

A set of points that lie on the same line

Points, lines, or segments that lie on the same plane

A part of a line with two endpoints.

Line

A straight, unbroken set of points that goes on forever. It h…

Collinear points

A set of points that lie on the same line

point

line

ray

line segment

a fixed location in space

a figure made up of points that extend forever in both direct…

a figure that has one endpoint and extends forever in the oth…

a piece of a line marked by two endpoints

point

a fixed location in space

line

a figure made up of points that extend forever in both direct…

Point

Plane

Line Segment

Ray

An exact location.

A flat surface that extends without end in all directions.

A portion of a line with two endpoints.

A portion of a line that extends in one direction.

Point

An exact location.

Plane

A flat surface that extends without end in all directions.

angle-angle similarity

angle

congruent

corresponding sides

if two angles of one triangle are congruent to two correspond…

in geometric figures, usually formed by two segments with a c…

exactly the same shape and size

sides in two or more figures that are images of each other wi…

angle-angle similarity

if two angles of one triangle are congruent to two correspond…

angle

in geometric figures, usually formed by two segments with a c…

parallel lines

perpendicular lines

intersecting lines

vertex

a pair of lines that are the same distance apart and will nev…

a "special" pair of intersecting lines that cross at a 90 deg…

a pair of lines that cross or will eventually cross

point where two rays meet to create an angle

parallel lines

a pair of lines that are the same distance apart and will nev…

perpendicular lines

a "special" pair of intersecting lines that cross at a 90 deg…

similarity

dilation

point of dilation / stretch point

scale factor / zoom factor

-same shape, but not necessarily the same size... -angles are co…

-a transformation where a point on a figure is stretched prop…

-the point of a figure that is stretched to form a dilation o…

-the number a side is multiplied by to make a bigger or small…

similarity

-same shape, but not necessarily the same size... -angles are co…

dilation

-a transformation where a point on a figure is stretched prop…

radius (regular polygon)

polygon

remote interior angles

linear scale factor

a line segment that connects the center of a regular polygon…

a two-dimensional closed figure of three or more line segment…

when a triangle has an exterior angles, these angles are the…

the ratio of similarity. the ratio of any pair of correspondi…

radius (regular polygon)

a line segment that connects the center of a regular polygon…

polygon

a two-dimensional closed figure of three or more line segment…

arc length

arc measure

center

central angle

the length of an arc

the measure in degrees of an arc's central angle

a fixed point from which all points on the circle are equidis…

an angle with its vertex at the center of a circle or polygon

arc length

the length of an arc

arc measure

the measure in degrees of an arc's central angle

Congruent Segments

Collinear Points

Coplanar Points

Midpoint

Segments that have the same measure

Points on the same line

Points on the same plane

A point that divides a segment into two congruent segments

Congruent Segments

Segments that have the same measure

Collinear Points

Points on the same line

legs

slope angle

law of sines

inverse tangent

the two sides of a right triangle that form the right angle.…

the acute angle a line forms with the x-axis on a coordinate…

used to find measurements in non-right triangles using the si…

the "undo" of the tangent function

legs

the two sides of a right triangle that form the right angle.…

slope angle

the acute angle a line forms with the x-axis on a coordinate…

Parallel Lines

Skew Lines

Corresponding Angles

Alternate Interior Angles

Lines that do not intersect and that lie in the same plane.

Lines that do not intersect and that do not line in the same…

Parallel Lines

Lines that do not intersect and that lie in the same plane.

Skew Lines

Lines that do not intersect and that do not line in the same…

undefined terms

point

line

plane

A word, ususally readily understood, that is not formually ex…

Points have no size. In a figure a point is represent by a do…

Lines extend indefinitely and have no tickness or width. In a…

Planes can be thought of as flat surfaces that extend indefin…

undefined terms

A word, ususally readily understood, that is not formually ex…

point

Points have no size. In a figure a point is represent by a do…

Midsegment

Coordinate Proof

Perpendicular Bisector

Equidistant

A segment that connects the midpoints of two sides of a trian…

A proof involving placing geometric figures in a coordinate p…

A line that is perpendicular to a segment at its midpoint.

Equal distance

Midsegment

A segment that connects the midpoints of two sides of a trian…

Coordinate Proof

A proof involving placing geometric figures in a coordinate p…

alpha

angle

arithmetic sequence

clinometer

a Greek letter often used to represent angle measure. Others…

formed by two rays joined at a common endpoint

an ordered sequence of mathematical terms in which a constant…

a device used to measure angles of elevation and depression

alpha

a Greek letter often used to represent angle measure. Others…

angle

formed by two rays joined at a common endpoint

bases

bisect

circle

concentric circles

the congruent parallel polygons that form the "top" and "bott…

to divide into two congruent parts

the set of all points on a flat surface that are the same dis…

circles that have the same center

bases

the congruent parallel polygons that form the "top" and "bott…

bisect

to divide into two congruent parts

Point

Line

Plane

Colinear

A location that has no size.

Straight path in two opposite directions without end. No thic…

A flat surface that extends without end. No thickness and inf…

Points on the same line.

Point

A location that has no size.

Line

Straight path in two opposite directions without end. No thic…

alternate interior angles

conjecture

line

proof by contradiction

inside the parallel lines, opposite sides of the transversal

An educated guess

A straight, unbroken set of points that goes on forever. It h…

a form of proof that establishes the truth or validity of a p…

alternate interior angles

inside the parallel lines, opposite sides of the transversal

conjecture

An educated guess

Regular Polygon

Parallelogram

Rectangle

Rhombus

a polygon with all sides and all angles equal

a quadrilateral with both pairs of opposite sides parallel

A parallelogram with four right angles

A parallelogram with four equal sides

Regular Polygon

a polygon with all sides and all angles equal

Parallelogram

a quadrilateral with both pairs of opposite sides parallel

counterexample

postulate

adjacent angles

complementary angles

an example that proves a statement false

an accepted statement of fact

are a pair of angles with a common vertex and a common side,…

Two angles whose sum is 90 degrees

counterexample

an example that proves a statement false

postulate

an accepted statement of fact

acute angle

angle

area

conjecture

an angle with measure greater than 0 degrees but less than 90…

formed by two rays at a common endpoint; in geometric figures…

on a flat surface, the number of non-overlapping square units…

an educated guess. often results from noticing a pattern duri…

acute angle

an angle with measure greater than 0 degrees but less than 90…

angle

formed by two rays at a common endpoint; in geometric figures…

complementary angles

supplementary angles

vertical angles

linear pair of angles

two angles that add up to 90 degrees

two angles that add up to 180 degrees

angles that are opposite from each other on intersecting line…

supplementary and adjacent

complementary angles

two angles that add up to 90 degrees

supplementary angles

two angles that add up to 180 degrees

point

line

line segment

ray

a location in space

straight pat of points that continues infinitely in both dire…

A part of a line with two endpoints

A part of a line that starts at one endpoint and extends fore…

point

a location in space

line

straight pat of points that continues infinitely in both dire…

acute angle

adjacent angles

angle

angle bisector

An angle that measures greater than 0 and less than 90 degrees.

Two angles in the same plane with a common vertex and a commo…

A figure formed by two rays with a common endpoint.

A ray that divides an angle into two congruent angles.

acute angle

An angle that measures greater than 0 and less than 90 degrees.

adjacent angles

Two angles in the same plane with a common vertex and a commo…

Point

Line

Plane

Coplanar Points

a specific location. It has no dimension and is represented b…

a connected straight path. It has no thickness and it continu…

a flat surface. It has no thickness and it extends forever in…

points that lie on the same plane

Point

a specific location. It has no dimension and is represented b…

Line

a connected straight path. It has no thickness and it continu…

Inductive Reasoning

Conjecture

Counter Example

Conditional Statement

The process of reasoning that a rule or statement is true bec…

A statement that is believed to be true

An example that proves a conjecture or statement false

A statement that can be written in the form "if p then q" whe…

Inductive Reasoning

The process of reasoning that a rule or statement is true bec…

Conjecture

A statement that is believed to be true

complementary angles

supplementary angles

congruent

linear pair

Two angles whose sum is 90 degrees

Two angles whose sum is 180 degrees

Having the same size and shape

Two adjacent angles formed by the intersection of two lines.…

complementary angles

Two angles whose sum is 90 degrees

supplementary angles

Two angles whose sum is 180 degrees

Perpendicular

Parallel

Right angle

Obtuse angle

Two lines that intersect to form right angles

Two lines that never intersect

measures 90 degrees

measures more than 90 but less than 180

Perpendicular

Two lines that intersect to form right angles

Parallel

Two lines that never intersect

width

line

acute angle

angle

one dimension of a two or three dimensional figure

a set of connected points continuing without end in both dire…

an angle with a measure less than 90 degrees

two rays that share an endpoint

width

one dimension of a two or three dimensional figure

line

a set of connected points continuing without end in both dire…

Point

Line

Plane

Ray

The most basic building block of geometry. It has no size; on…

A straight, continuous arrangement of infinitely many points.…

Length and width, but no thickness. A flat surface that exten…

A portion of a line that starts at a point (endpoint) and con…

Point

The most basic building block of geometry. It has no size; on…

Line

A straight, continuous arrangement of infinitely many points.…

Midpoint

Colinear

Straight Angle

Acute Angle

It is a midpoint iff it divides a segment into two congruent…

3 or more points on the same line

Sides of a straight angle form a line

Less then a right angle

Midpoint

It is a midpoint iff it divides a segment into two congruent…

Colinear

3 or more points on the same line

between

congruent segments

construction

undefined term

in the middle, but not necessarily half way

Segments that have the same length (same size and shape)

to use tools to draw an object that is more precise

a word without a formal definition: point, line, and plane

between

in the middle, but not necessarily half way

congruent segments

Segments that have the same length (same size and shape)

Vertical Angles

Linear Pair

Supplementary Angles

Angle

Two nonadjacent angles who share a common initial point and t…

Two adjacent angles that together form a line.

Two angles whose sum is 180 degrees.

Formed when two rays share an initial point.

Vertical Angles

Two nonadjacent angles who share a common initial point and t…

Linear Pair

Two adjacent angles that together form a line.

Volume

Hypotenuse

Polygon

Area

Capacity to hold, measured in cubic units.

In a right triangle, the side opposite the 90 degree angle.

A many-sided plane closed figure.

The space within a shape, measured in square units.

Volume

Capacity to hold, measured in cubic units.

Hypotenuse

In a right triangle, the side opposite the 90 degree angle.

Lines

Planes

Ray

Coplanar

a series of points that extends in two opposite directions wi…

a flat surface with no thickness

is the part of a line consisting of one endpoint and all the…

points and lines in the same planes

Lines

a series of points that extends in two opposite directions wi…

Planes

a flat surface with no thickness