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Same-Side Interior Angles

Same-Side Exterior Angles

Corresponding Angles

Corresponding Angles Postulate

Pairs of angles formed when a third line (a transversal) cros…

Pairs of angles formed when a third line (a transversal) cros…

Angles that are in the same position. When a transversal inte…

If two parallel lines are cut by a transversal, then the corr…

Same-Side Interior Angles

Pairs of angles formed when a third line (a transversal) cros…

Same-Side Exterior Angles

Pairs of angles formed when a third line (a transversal) cros…

Parallel lines

Perpendicular lines

Adjacent angles

Vertical angles

Two lines in a plane that do not intersect

Two lines that intersect to form right angles

Angles that have a common vertex and a common side, but no co…

The opposite angles formed by two intersecting lines, with a…

Parallel lines

Two lines in a plane that do not intersect

Perpendicular lines

Two lines that intersect to form right angles

Parallel lines

Equal

Alternate interior angles

Alternate exterior angles

Lines will never meet that they are always equidistant.

the angles that occupy the same relative position at each int…

When two lines are crossed by another line (called the Transv…

When two lines are crossed by another line (called the Transv…

Parallel lines

Lines will never meet that they are always equidistant.

Equal

the angles that occupy the same relative position at each int…

right angle

obtuse angle

straight angle

complimentary angles

an angle that is exactly 90 degrees.

an angle that is greater than 90 degrees and less than 180 de…

an angle that measures exactly 180 degrees.

2 Angles that add up to 90 degrees.

right angle

an angle that is exactly 90 degrees.

obtuse angle

an angle that is greater than 90 degrees and less than 180 de…

parallel lines

perpendicular lines

obtuse angle

acute angle

lines that never intersect

intersecting lines that form right angles

angle that measures more than 90 degrees

angle that measures less than 90 degrees

parallel lines

lines that never intersect

perpendicular lines

intersecting lines that form right angles

Acute Angle

Right Angle

Obtuse Angle

Line

An angle that is open less than a right angle.

An angle that makes a square corner.

An angle that is open more than a right angle.

Is a set of points that is endless in two directions.

Acute Angle

An angle that is open less than a right angle.

Right Angle

An angle that makes a square corner.

line segnment

endpoints

ray

angle

part of a line, has two endpoints

show that a line segment stops and doesn't keep on going

part of a line, keeps on going in one direction, has only one…

two rays joined together

line segnment

part of a line, has two endpoints

endpoints

show that a line segment stops and doesn't keep on going

transversal

corresponding angles

alternate interior angles

alternate exterior angles

a line that crosses 2 other lines; sometimes the other 2 line…

when 2 lines are crossed by a transversal: angles located in…

when 2 lines are crossed by a transversal: angles located on…

when 2 lines are crossed by a transversal: angles located on…

transversal

a line that crosses 2 other lines; sometimes the other 2 line…

corresponding angles

when 2 lines are crossed by a transversal: angles located in…

Parallel lines

Perpendicular lines

Skew lines

Parallel planes

Are coplanar and do not interset.

Intersect at 90 degree angles.

Are not coplanar. These lines are not parallel and do not int…

Are planes that do not intersect.

Parallel lines

Are coplanar and do not interset.

Perpendicular lines

Intersect at 90 degree angles.

parallel lines

perpendicular lines

obtuse angle

acute angle

lines that never intersect

intersecting lines that form right angles

angle that measures more than 90 degrees

angle that measures less than 90 degrees

parallel lines

lines that never intersect

perpendicular lines

intersecting lines that form right angles

Parallel lines

Perpendicular lines

Adjacent angles

Vertical angles

Two lines in a plane that do not intersect

Two lines that intersect to form right angles

Angles that have a common vertex and a common side, but no co…

The opposite angles formed by two intersecting lines, with a…

Parallel lines

Two lines in a plane that do not intersect

Perpendicular lines

Two lines that intersect to form right angles

line

line segment

ray

point

a straight path that goes on forever in two directions

part of a line with two endpoints

a straight path that begins at a point and goes on forever in…

a location on a flat plane

line

a straight path that goes on forever in two directions

line segment

part of a line with two endpoints

Adjacent angles

Complementary angles

Supplementary angles

Congruent angles

Two angles having the same vertex and sharing 1 side.

Two angles, adjacent or non adjacent whose sum is 90 degrees

Two angles who sum is 180 degrees

angles having the same measure

Adjacent angles

Two angles having the same vertex and sharing 1 side.

Complementary angles

Two angles, adjacent or non adjacent whose sum is 90 degrees

Vertex

Adjacent

Vertical Angles

Linear Pair

the highest or lowest point on a curve

next to or adjoining something else

a pair of non-adjacent angles formed when two lines intersect

a pair of adjacent angles formed when two lines intersect

Vertex

the highest or lowest point on a curve

Adjacent

next to or adjoining something else

right angle

obtuse angle

straight angle

acute angle

angle that measures exactly 90 degrees.

angle that is >90 degrees and <180 degrees.

angle that measures exactly 180 degrees.

angles whose measure is >0 degrees and <90 degrees

right angle

angle that measures exactly 90 degrees.

obtuse angle

angle that is >90 degrees and <180 degrees.

angle (угол)

vertex (вершина)

sides (стороны)

acute angle (острый угол)

formed by 2 rays with the same end point (образован двумя луч…

the endpoint of 2 rays (общая точка двух лучей)

2 rays of an angle

> 0⁰ and < 90⁰

angle (угол)

formed by 2 rays with the same end point (образован двумя луч…

vertex (вершина)

the endpoint of 2 rays (общая точка двух лучей)

Addition Postulate

Segment Addition Postulate

Angles

Measure of angle ABC

if points lie within angle PQR then the measure of PQS plus m…

two rays that share an endpoint called the vertex

Addition Postulate

if points lie within angle PQR then the measure of PQS plus m…

Segment Addition Postulate

adjacecent angles

vertical angles

supplementary angles

complementary angles

must share a common side and vertex

non-adjacent angles formed by intersecting lines

angle measures add up to 180 degrees

angle measures add up to 90 degrees

adjacecent angles

must share a common side and vertex

vertical angles

non-adjacent angles formed by intersecting lines

Angle

Parallel lines

Perpendicular Lines

Obtuse Angle

Two non-collinear rays with a common endpoint

Two lines that never touch

Two lines that intersect at a 90 degree angle

An angle that measures more than 90 degrees and less than 180…

Angle

Two non-collinear rays with a common endpoint

Parallel lines

Two lines that never touch

Angle

Perpendicular Lines

Parallel Lines

Line

Two rays that meet at the same point

Two lines, line segments, or rays that intersect at 90 degree…

Two lines that will never intersect

A straight segment that goes on forever in both directions

Angle

Two rays that meet at the same point

Perpendicular Lines

Two lines, line segments, or rays that intersect at 90 degree…

Perpendicular lines

Parallel lines

Skew lines

adjacent angles

the angles formed by two intersecting lines measure 90 degrees

lines in the same plane that do not intersect at all

do not intersect and are not parallel

have a common vertex and a common side, but no common interio…

Perpendicular lines

the angles formed by two intersecting lines measure 90 degrees

Parallel lines

lines in the same plane that do not intersect at all

right angle

obtuse angle

straight angle

complementary angles

angle that measures exactly 90 degrees.

angle that is >90 degrees and <180 degrees.

angle that measures exactly 180 degrees.

Two angles whose sum is 90 degrees

right angle

angle that measures exactly 90 degrees.

obtuse angle

angle that is >90 degrees and <180 degrees.

Parallel Lines

Intersecting Lines

Supplementary Angles

Complementary Angles

They are lines that are the same distance apart and do not in…

Lines that meet or cross at a common point.

Angles whose sum measures 180º .

Angles whose sum measures 90º.

Parallel Lines

They are lines that are the same distance apart and do not in…

Intersecting Lines

Lines that meet or cross at a common point.

right angle

obtuse angle

straight angle

acute angle

angle that measures exactly 90 degrees.

angle that is more than 90 degrees and less than 180 degrees.

angle that measures exactly 180 degrees.

angles whose measure is greater than 0 degrees and less than…

right angle

angle that measures exactly 90 degrees.

obtuse angle

angle that is more than 90 degrees and less than 180 degrees.

point

line segment

line

ray

An exact position or location on a plane surface

When two points are connected with a straight... line

Has no beginning point or end point. Imagine it continuing in…

Starts out at a point and continues off to infinity. We can s…

point

An exact position or location on a plane surface

line segment

When two points are connected with a straight... line

line

segment

plane

parallel lines

A straight path that extends without end in both directions

A part of a line with 2 distinct end points

A flat surface that extends without end

Lines in the same plane that do not intersect. They remain th…

line

A straight path that extends without end in both directions

segment

A part of a line with 2 distinct end points

Parallel lines

Angle congruence

Transversal

Corresponding angles

Co planar lines that do not intrrsect

Angles that are equal =

A line that crosses two or more lines .

Angles that are in same location at each intersection

Parallel lines

Co planar lines that do not intrrsect

Angle congruence

Angles that are equal =

point, end point

line

line segment

angle

an exact location in space

a straight path that goes on without end in both directions

part of a line that has two endpoints

formed when two line segments share the same endpoint

point, end point

an exact location in space

line

a straight path that goes on without end in both directions

Point

Line

Line segment

Ray

a position in space; named with a capital letter

a straight path of points with no endpoints; names with a low…

part of a line with 2 endpoints; named with capital letters.

part of a line with 1 endpoint; named with capital letters. T…

Point

a position in space; named with a capital letter

Line

a straight path of points with no endpoints; names with a low…

similar figures

congruent figures

line

plane

same exact shape but not same size

same exact shape and same exact size

a line is a straight continuous arrangement of infinitely man…

A plane has a length and width, but no thickness. It is like…

similar figures

same exact shape but not same size

congruent figures

same exact shape and same exact size

Right Angle

Obtuse Angle

Acute Angle

Straight Angle

an angle that measures 90 degrees

an angle that measures between 90 and 180 degrees

an angle that measures less than 90 degrees

an angle that measures 180 degrees

Right Angle

an angle that measures 90 degrees

Obtuse Angle

an angle that measures between 90 and 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…

Parallel Lines

Skew Lines

Parallel Planes

Transversal

Lines in the same plane that do not intersect.

Lines that lie in different planes that are neither parallel…

planes that do not intersect

A line that intersects two or more lines in a plane at differ…

Parallel Lines

Lines in the same plane that do not intersect.

Skew Lines

Lines that lie in different planes that are neither parallel…

line segment

ray

line

parallel

part of a line with two endpoints

part of a a straight line extending out in one direction from…

a collection of points in a straight path that goes on and on…

never cross or meet

line segment

part of a line with two endpoints

ray

part of a a straight line extending out in one direction from…