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alternate exterior angles

alternate interior angles

corresponding angles

parallel lines

Angles that lie outside a pair of lines and on opposite sides…

nonadjacent interior angles that lie on opposite sides of the…

Angles that lie on the same side of the transversal and in co…

lines in a plane that do not intersect

alternate exterior angles

Angles that lie outside a pair of lines and on opposite sides…

alternate interior angles

nonadjacent interior angles that lie on opposite sides of the…

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…

Counterexample

Good Definition has

Parallel Lines

Perpendicular Lines

something that would fit your definition, but is not what you…

classification, differentiation, and can be tested.

exist in the same plane that never meet. We use II to represe…

must meet at a 90° angle. We use ⊥ to represent it.

Counterexample

something that would fit your definition, but is not what you…

Good Definition has

classification, differentiation, and can be tested.

angle

interior of an angle

exterior of an angle

acute angle

a figure formed by two rays with a common endpoint called the…

the set of all points between the sides of the angle

the set of all points outside the angle

an angle that measures greater than 0 degrees and less than 9…

angle

a figure formed by two rays with a common endpoint called the…

interior of an angle

the set of all points between the sides of the angle

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…

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…

parallel lines

skew lines

parallel planes

transversal

lines in the same plane that never intersect

do not intersect and do not lie on the same plane

planes that do not intersect

a line that intersects two or more lines

parallel lines

lines in the same plane that never intersect

skew lines

do not intersect and do not lie on the same plane

Parallel Lines

Skew Lines

Transversal

Interior Angles

Two lines in the same plane that do not intersect

Two lines in different planes that do not intersect

A line that intersects two or more coplanar lines

Angles that lie in the region between the two lines

Parallel Lines

Two lines in the same plane that do not intersect

Skew Lines

Two lines in different planes that do not intersect

acute

right

obtuse

straight

_______ angles measure between 0-90 degrees

______ angles measure exactly 90 degrees

______ angles measure between 90 and 180 degrees

______ angles measures exactly 180 degrees

acute

_______ angles measure between 0-90 degrees

right

______ angles measure exactly 90 degrees

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.

Parallel Lines

Skew Lines

Transversal

Interior Angles

Two lines in the same plane that do not intersect

Two lines in different planes that do not intersect

A line that intersects two or more coplanar lines

Angles that lie in the region between the two lines

Parallel Lines

Two lines in the same plane that do not intersect

Skew Lines

Two lines in different planes that do not intersect

centroid

conditional

hypothesis

conclusion

the point of intersection of the medians of a triangle

a type of logical statement that has two parts, a hypothesis…

the if part of a conditional statement

the then part of a conditional statement

centroid

the point of intersection of the medians of a triangle

conditional

a type of logical statement that has two parts, a hypothesis…

Transversal

Interior

Exterior

Alternate Interior Angles

A line, ray, or segment that intersects two or more coplanar…

Area between the lines

Area outside the lines

Angles 2 and 7... Or... Angles 3 and 6

Transversal

A line, ray, or segment that intersects two or more coplanar…

Interior

Area between the lines

Acute angle

Angle

congruent angles

Measure of an angle

an angle that measures between 0 and 90 degrees

A figure formed by two rays with a common endpoint

angles that have the same measure

The number of degrees of an angle . Shown by the notations m∠…

Acute angle

an angle that measures between 0 and 90 degrees

Angle

A figure formed by two rays with a common endpoint

parallel lines

skew lines

transversal

alternate interior angles

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

Lines which do not lie in the same plane.

A line that intersects 2 or more lines.

Non-adjacent angles that lie on the opposite sides of a trans…

parallel lines

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

skew lines

Lines which do not lie in the same plane.

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…

Regular polygon

perimeter of a polygon

similar figures

pythagorean theorem

a polygon with all sides and all angles equal

The sum of the measures of all sides of a polygon

Figures that have the same shape but not necessarily the same…

a²+b²=c²... States that in a right triangle, the square of the h…

Regular polygon

a polygon with all sides and all angles equal

perimeter of a polygon

The sum of the measures of all sides of a polygon

Alternate interior angles

Alternate exterior angles

Consecutive interior angles

Corresponding angles

In the figure,transversal t intersects lines p and q. What ar…

What are angles1 & 2

Alternate interior angles

In the figure,transversal t intersects lines p and q. What ar…

Alternate exterior angles

What are angles1 & 2

Parallel Lines

Skew Lines

Parallel Planes

Perpendicular Lines

Lines that do not intersect and are coplanar. Lines that are…

Lines that do not intersect and are not coplanar.

Planes that do not intersect

Lines that intersect at a 90 degree angle

Parallel Lines

Lines that do not intersect and are coplanar. Lines that are…

Skew Lines

Lines that do not intersect and are not coplanar.

parallel lines

perpendicular lines

skew lines

perpendicular bisector

lines which are coplanar and do not intersect

lines which intersect at 90˚ angles

lines which are not coplanar

a line perpendicular to a segment at the segment's midpoint

parallel lines

lines which are coplanar and do not intersect

perpendicular lines

lines which intersect at 90˚ angles

Acute Angle

Alternate Exterior Angeles

Alternate Interior Angles

Angle Addition Postulate

An angle that is less than 90°.

When two lines are crossed by another line (which is called t…

When two lines are crossed by another line (which is called t…

The angle addition postulate states that if B is in the inter…

Acute Angle

An angle that is less than 90°.

Alternate Exterior Angeles

When two lines are crossed by another line (which is called t…

parallel lines

skew lines

corresponding angles

alternate interior angles

Coplanar lines that do not intersect

Non-coplanar lines that do not intersect

congruent angles in corresponding positions of parallel lines…

congruent angles that lie between parallel lines and are loca…

parallel lines

Coplanar lines that do not intersect

skew lines

Non-coplanar lines that do not intersect

Polygon

Equilateral Polygon

Equiangular Polygon

Regular Polygon

A closed plane figure where the edges are not curved and each…

A polygon with all congruent sides.

A polygon with all congruent angles.

A polygon that is both equilateral and equiangular.

Polygon

A closed plane figure where the edges are not curved and each…

Equilateral Polygon

A polygon with all congruent sides.

parallel lines

perpendicular lines

skew lines

parallel planes

coplanar lines that do not intersect

lines that intersect at a 90 degree angle

lines that are not coplanar, not parallel and do not intersect

planes that do not intersect

parallel lines

coplanar lines that do not intersect

perpendicular lines

lines that intersect at a 90 degree angle

sketch

draw

construct

perpendicular bisector

to create a figure without measurement tools or compass

to create a figure using measurement tools such as a ruler an…

to create a figure with a compass and straight edge but no me…

a line perpendicular to a side of the triangle at its midpoint

sketch

to create a figure without measurement tools or compass

draw

to create a figure using measurement tools such as a ruler an…

Parallel lines

Skew lines

Parallel planes

Transversal

Coplanar lines that do not intersect

Lines that do not intersect and are not coplanar

Planes that do not intersect

A line that intersects two or more coplanar lines at two diff…

Parallel lines

Coplanar lines that do not intersect

Skew lines

Lines that do not intersect and are not coplanar

parallel lines

perpendicular lines

skew lines

parallel planes

coplanar lines that do not intersect

lines that intersect at a 90 degree angle

lines that are not coplanar, not parallel and do not intersect

planes that do not intersect

parallel lines

coplanar lines that do not intersect

perpendicular lines

lines that intersect at a 90 degree angle

Parrallel lines

Perpendicular lines

Skew lines

Parallel planes

Coplanar lines that do not intersect ( have same slope).

Lines that form 4 right angles and have a negative reciprocal…

Non coplanar lines that do not intersect

Planes that do not intersect

Parrallel lines

Coplanar lines that do not intersect ( have same slope).

Perpendicular lines

Lines that form 4 right angles and have a negative reciprocal…

ADJACENT... Sketch a pair of adjacent ang…

VERTICAL... What forms vertical angles?... S…

LINEAR PAIR... Since the sum of a linear…

COMPLEMENTARY... If an angle is measured…

Angle CAB is adjacent to Angle DAB.

Intersecting lines.

No. Supplementary angles do have a sum of 180 degrees but the…

90 - x

ADJACENT... Sketch a pair of adjacent ang…

Angle CAB is adjacent to Angle DAB.

VERTICAL... What forms vertical angles?... S…

Intersecting lines.

Parallel Lines

Parallel Planes

Skew Lines

Transversal

Coplanar lines that never intersect.

Planes that never intersect.

Non-coplanar lines that never intersect.

A line that intersects two or more lines in a plane.

Parallel Lines

Coplanar lines that never intersect.

Parallel Planes

Planes that never intersect.

quadrilateral

trapezoid

parallelogram

rhombus

a polygon with 4 sides

A quadrilateral with exactly one pair of parallel sides

a quadrilateral with 2 pairs of parallel sides

a parallelogram with 4 congruent sides

quadrilateral

a polygon with 4 sides

trapezoid

A quadrilateral with exactly one pair of parallel sides

Corresponding Angles

Alternate Interior Angles

Consecutive Interior Angles

Alternate Exterior Angles

Angles that have the same position on two different parallel…

nonadjacent interior angles that lie on opposite sides of the…

Angles that are on the same side of a transversal on the inte…

Angles that lay outside the parallel lines and are on opposit…

Corresponding Angles

Angles that have the same position on two different parallel…

Alternate Interior Angles

nonadjacent interior angles that lie on opposite sides of the…

Nonadjacent exterior angles that lie o…

Nonadjacent interior angles that lie o…

A line that is added to a diagram to h…

Angles on the same side of the transve…

Alternate Exterior Angles

Alternate Interior Angles

Auxiliary Line

Corresponding Angles

Nonadjacent exterior angles that lie o…

Alternate Exterior Angles

Nonadjacent interior angles that lie o…

Alternate Interior Angles

Algebraic Proof

Alternate Exterior Angles

Alternate Interior Angles

Consecutive Interior Angles

A proof that is made up of a series of algebraic statements;…

Angles that are outside the parallel lines and on different s…

Angles that are inside the parallel lines and on different si…

Angles that are inside the parallel lines and on the same sid…

Algebraic Proof

A proof that is made up of a series of algebraic statements;…

Alternate Exterior Angles

Angles that are outside the parallel lines and on different s…

acute angle

angle bisector

collinear points

congruent angles

an angle whose measure is greater than 0 degrees and less tha…

a ray that divides an angle into two adjacent angles that are…

Points that lie on the same line.

angles that have equal measures

acute angle

an angle whose measure is greater than 0 degrees and less tha…

angle bisector

a ray that divides an angle into two adjacent angles that are…

Line

Line Segment

Ray

Plane

A one dimensional geometric figure that extends without end i…

A part of a line with two endpoints; named using two points

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

a flat surface that extends forever; named using three letters

Line

A one dimensional geometric figure that extends without end i…

Line Segment

A part of a line with two endpoints; named using two points

parallel lines

perpendicular lines

parallel planes

line perpendicular to a plane

lines in the same plane that never intersect

Lines that intersect to form right angles

planes that do not intersect

a line that intersects the plane in a point and is perpendicu…

parallel lines

lines in the same plane that never intersect

perpendicular lines

Lines that intersect to form right angles

CPCTC

SSS congruence postulate

Included angle

SAS congruence postulate

given as a reason for a step in a geometry proof, CPCTC stand…

if three sides of one triangle are congruent to three sides o…

the angle between two sides of a triangle

if two sides and the included angle of one triangle are congr…

CPCTC

given as a reason for a step in a geometry proof, CPCTC stand…

SSS congruence postulate

if three sides of one triangle are congruent to three sides o…

Parallel Lines

Perpendicular Lines

Skew Lines

Transversal

Coplanar lines that do not intersect.

Lines that intersect to form a right angle.

Non-coplanar lines that do not intersect.

A line that intersect two distinct lines at two distinct poin…

Parallel Lines

Coplanar lines that do not intersect.

Perpendicular Lines

Lines that intersect to form a right angle.

Alternate Interior Angles

Same-Side Interior Angles

Corresponding Angles

Parallel Lines

Opposite Interior angles of parallel lines

Same side angles inside parallel lines

Angles on the same side, one Interior and another exterior

2 lines that don't intersect

Alternate Interior Angles

Opposite Interior angles of parallel lines

Same-Side Interior Angles

Same side angles inside parallel lines

Acute angle

Obtuse angle

Straight angle

Right Triangle

An angle less than 90 degrees

an angle that measures between 90 and 180 degrees

an angle that measures 180 degrees

a triangle with one right angle

Acute angle

An angle less than 90 degrees

Obtuse angle

an angle that measures between 90 and 180 degrees

Regular polygon

Inscribed (polygon)

Center (regular polygon)

Radius (regular polygon)

a convex polygon that is both equilateral and equiangular

a polygon inside a circle with each vertex of the polygon fal…

a coplanar point that is equidistant from every vertex of a r…

the distance from the center to a vertex of a regular polygon

Regular polygon

a convex polygon that is both equilateral and equiangular

Inscribed (polygon)

a polygon inside a circle with each vertex of the polygon fal…

alternate exterior angles

alternate interior angles

consecutive interior angles

corresponding angles

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

alternate exterior angles

Two angles that are formed by two lines and a transversal tha…

alternate interior angles

Two angles that are formed by two lines and a transversal tha…

alternate exterior angles

alternate interior angles

auxiliary lines

corresponding angles

nonadjacent exterior angles that lie on opposite sides of the…

nonadjacent interior angles that lie on opposite sides of the…

a line that is added to a diagram to help explain relationshi…

angles that lie on the same side of the transversal t and in…

alternate exterior angles

nonadjacent exterior angles that lie on opposite sides of the…

alternate interior angles

nonadjacent interior angles that lie on opposite sides of the…