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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…

attribute

congruent angles

isosceles triangle

scalene triangle

A characteristic of a figure.

Angles of a figure that are equal in measure.

A triangle with 2 equal sides of the same length.

A triangle with no congruent sides.

attribute

A characteristic of a figure.

congruent angles

Angles of a figure that are equal in measure.

Angle

Circle

Perpendicular Lines

Parallel Lines

The amount of turn between two straight lines that have a com…

Two dimensional shape created by drawing a curve that is alwa…

Two lines that create a 90 degree angle when they intersect

Two lines on a plane that will never meet. They are always th…

Angle

The amount of turn between two straight lines that have a com…

Circle

Two dimensional shape created by drawing a curve that is alwa…

model

polygon

quadrilateral

triangle

a three-dimensional representation of a thing or concept.

2-D shape that has 3 or more straight sides

a 2D shape with four sides and four angles

a polygon with three sides and three angles

model

a three-dimensional representation of a thing or concept.

polygon

2-D shape that has 3 or more straight sides

perimeter

area

reflection

translation

the distance around a closed figure

the number of square units needed to cover a surface

a transformation that produces a mirror image of a figure

a transformation that moves a figure by sliding each of the p…

perimeter

the distance around a closed figure

area

the number of square units needed to cover a surface

point

line segment

line

ray

a small dot on a surface, which has no dimension

a straight row of points that starts at one point and ends at…

a straight row of points that goes on forever in both directi…

a straight row of points that starts at one point and goes on…

point

a small dot on a surface, which has no dimension

line segment

a straight row of points that starts at one point and ends at…

Polygon

Regular Polygon

Triangle

Quadrilateral

2D shape... Closed... Three or more side

A polygon whose lines are all the same length

A three sided polygon

A four-sided polygon

Polygon

2D shape... Closed... Three or more side

Regular Polygon

A polygon whose lines are all the same length

Line

Line Segment

Ray

Transversal

a set of points that moves forever in opposite directions ↔

a part of a line that has two end points. ... (Measureable)

a set of points with one end point

a line that intersects (touches) 2 or more lines

Line

a set of points that moves forever in opposite directions ↔

Line Segment

a part of a line that has two end points. ... (Measureable)

Point

Line

Line segment

Planar

mathematical object with no size, which can be specified in -…

A straight path that extends without end in opposite directio…

A part of a line between two endpoints.

Lying in a plane

Point

mathematical object with no size, which can be specified in -…

Line

A straight path that extends without end in opposite directio…

Acute angle

Angle

Hexagon

Intersecting lines

An angle that measures less than 90 degrees.

A figure formed by 2 rays that have the same endpoint.

A six sided figure.

Lines that meet or cross at a common point.

Acute angle

An angle that measures less than 90 degrees.

Angle

A figure formed by 2 rays that have the same endpoint.

a polygon with all equal sides and equ…

a quadrilateral that has opposite side…

a parallelogram in which all four side…

figures that have the same shape but m…

regular polygon

rectangle

rhombus

similar figures

a polygon with all equal sides and equ…

regular polygon

a quadrilateral that has opposite side…

rectangle

angle

endpoint

octagon

parallelogram

two rays sharing the same endpoint

the point at the beginning of a ray

a polygon with 8 sides and 8 angles

a quadrilateral that has both pairs of opposite sides paralle…

angle

two rays sharing the same endpoint

endpoint

the point at the beginning of a ray

Acute angle

Angle

Hexagon

Intersecting lines

An angle that measures less than 90 degrees.

A figure formed by 2 rays that have the same endpoint.

A six sided figure.

Lines or rays that meet or cross at a vertices

Acute angle

An angle that measures less than 90 degrees.

Angle

A figure formed by 2 rays that have the same endpoint.

adjacent angle

acute angle

angle bisector

angle

Two angles that share a common vertex and side, but have no c…

An angle that has a measure greater than 0⁰ and less than 90⁰

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that... have th…

adjacent angle

Two angles that share a common vertex and side, but have no c…

acute angle

An angle that has a measure greater than 0⁰ and less than 90⁰

area

perimeter

parallelogram

rectangle

The number of square units needed to fill up a region on a fl…

The distance around a figure on a flat surface.

A quadrilateral with two pairs of parallel sides.

A quadrilateral with four right angles.

area

The number of square units needed to fill up a region on a fl…

perimeter

The distance around a figure on a flat surface.

Adjacent angle

Acute angle

Angle bisector

Angle

Two angles that share a common vertex and side, but have no c…

An angle that has a measure greater than 0⁰ and less than 90⁰

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that have th…

Adjacent angle

Two angles that share a common vertex and side, but have no c…

Acute angle

An angle that has a measure greater than 0⁰ and less than 90⁰

parallel lines

skew lines

parallel planes

transversal

Coplanar lines that do not intersect.

Lines that do not intersect and are not coplanar.

Two planes that do not intersect.

A line that intersects two coplanar lines at two distinct poi…

parallel lines

Coplanar lines that do not intersect.

skew lines

Lines that do not intersect and are not coplanar.

conclusion

biconditional statement

conjecture

conditional statement

The "then" part of a conditional statement written in if-then…

A statement that contains the phrase "if and only if"

An unproven statement that is based on observations

A logical statement that has a hypothesis and a conclusion

conclusion

The "then" part of a conditional statement written in if-then…

biconditional statement

A statement that contains the phrase "if and only if"

angle of depression

angle of elevation

cosine

geometric mean

The angle that a downward line of sight makes with a horizont…

The angle that an upward line of sight makes with a horizonta…

A trigonometric ratio for acute angles that involves the leng…

The positive number x that satisfies a/x = x/b... So, x² = ab an…

angle of depression

The angle that a downward line of sight makes with a horizont…

angle of elevation

The angle that an upward line of sight makes with a horizonta…

Point

Line

Collinear

Noncollinear

The simplest figure in geometry, pictured by a dot.

A straight line extending in both directions without end.

Two or more points that lie on the same line.

Points not on the same line.

Point

The simplest figure in geometry, pictured by a dot.

Line

A straight line extending in both directions without end.

adjacent angle

acute angle

angle bisector

angle

Two angles that share a common vertex and side, but have no c…

An angle that has a measure greater than 0⁰ and less than 90⁰

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that... have th…

adjacent angle

Two angles that share a common vertex and side, but have no c…

acute angle

An angle that has a measure greater than 0⁰ and less than 90⁰

line

line segment

ray

perpendicular lines

a straight path that goes on forever in both directions

a section of a line that has a beginning and end

a straight path with a beginning point and no end.

lines that meet or cross and form right angles

line

a straight path that goes on forever in both directions

line segment

a section of a line that has a beginning and end

Right Triangle

Scalene Triangle

Straight Angle

Supplementary Angles

A triangle with a 90 degree angle

A triangle with no equal sides or equal angles

An angle that is 180 degrees

Two angles when they add up to 180 degrees

Right Triangle

A triangle with a 90 degree angle

Scalene Triangle

A triangle with no equal sides or equal angles

parallelogram

base

square

face

4 sided shape with straight sides and opposite sides that are…

the bottom of a 3D figure

4 sided shape with equal sides and angles

the surface

parallelogram

4 sided shape with straight sides and opposite sides that are…

base

the bottom of a 3D figure

Triangle

Scalene Triangle

Equilateral Triangle

Right Angle Triangle

A polygon with three sides.

A triangle with no congruent sides

A triangle with three congruent sides

A triangle in which one angle is a right angle (a 90-degree a…

Triangle

A polygon with three sides.

Scalene Triangle

A triangle with no congruent sides

base angles of an isosceles triangle

base of an isosceles triangle

coordinate proof

corollary to a theorem

The two angles adjacent to the base of an isosceles triangle.

The side of an isosceles triangle that is not one of the legs.

A style of proof that involves placing geometric figures in a…

A statement that can be proved easily using the theorem.... The…

base angles of an isosceles triangle

The two angles adjacent to the base of an isosceles triangle.

base of an isosceles triangle

The side of an isosceles triangle that is not one of the legs.

Quadrilateral

Trapezoid

Rhombus

Square

A closed shape that has 4 sides, 4 angles and whose angles ad…

A 4 sided shape that has exactly one pair of parallel sides

4 equal sides, 4 angles, two pair of opposite sides that are…

4 equal sides, 4 right angles, two pair of opposite sides tha…

Quadrilateral

A closed shape that has 4 sides, 4 angles and whose angles ad…

Trapezoid

A 4 sided shape that has exactly one pair of parallel sides

altitude of a triangle

Centroid

Circumcenter

Concurrent

The perpendicular segment from a vertex of a ... triangle to the…

The point of concurrency of the three medians of a triangle.

The point of concurrency of the three ... perpendicular bisector…

Three or more lines, rays, or segments that ... intersect in the…

altitude of a triangle

The perpendicular segment from a vertex of a ... triangle to the…

Centroid

The point of concurrency of the three medians of a triangle.

Line

Naming a Line

Line Segment

Ray

A straight path that goes on forever.

A line is Named 2 points and the symbol. <------>

The part of a line between the 2 points on the line

Part of a line having only 1 endpoint.

Line

A straight path that goes on forever.

Naming a Line

A line is Named 2 points and the symbol. <------>

line

line segment

ray

parallel lines

A continuous extent of length, straight or curved, without an…

part of a line with two endpoints

A part of a line, with one endpoint, that continues without e…

lines in the same plane that never intersect

line

A continuous extent of length, straight or curved, without an…

line segment

part of a line with two endpoints

adjacent angle

acute angle

angle bisector

angle

Two angles that share a common vertex and side, but have no c…

An angle that has a measure greater than 0⁰ and less than 90⁰

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that... have th…

adjacent angle

Two angles that share a common vertex and side, but have no c…

acute angle

An angle that has a measure greater than 0⁰ and less than 90⁰

Polygon

Congruent

Regular Polygon

Triangle

A closed figure made of line segments that do not intersect.

Figures, sides or angles that are equal (the same).

A polygon with all sides congruent.

A polygon with 3 sides.

Polygon

A closed figure made of line segments that do not intersect.

Congruent

Figures, sides or angles that are equal (the same).

adjacent angle

angle bisector

angle

complementary angles

Two angles that share a common vertex and side, but have no c…

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that... have th…

Two angles whose measures have a sum of 90⁰

adjacent angle

Two angles that share a common vertex and side, but have no c…

angle bisector

A ray that divides an angle into two angles that are congruent

base angles of a trapezoid

bases of a trapezoid

diagonal

equiangular polygon

Either pair of consecutive angles whose common side is a base…

The parallel sides of a trapezoid

A segment that joins two nonconsecutive vertices of a polygon

A polygon in which all angles are congruent

base angles of a trapezoid

Either pair of consecutive angles whose common side is a base…

bases of a trapezoid

The parallel sides of a trapezoid

Apothem of a Regular Polygon

Arc Length

Axis of Revolution

Cavalieri's Principle

The distance from the center to any side of a... regular polygon

A portion of the circumference of a circle

The line around which a two-dimensional shape is rotated to f…

If two solids have the same height and the same cross-section…

Apothem of a Regular Polygon

The distance from the center to any side of a... regular polygon

Arc Length

A portion of the circumference of a circle

Polygon

Congruent

Regular Polygon

Triangle

A closed figure made of line segments that do not intersect.

Figures, sides or angles that are equal (the same).

A polygon with all sides congruent.

A polygon with 3 sides.

Polygon

A closed figure made of line segments that do not intersect.

Congruent

Figures, sides or angles that are equal (the same).

vertex

polygon

quadrilateral

parallelogram

an endpoint where two rays or line segments meet

a closed shape made up of line segments

a four-sided polygon

a quadrilateral with 2 pairs of parallel sides

vertex

an endpoint where two rays or line segments meet

polygon

a closed shape made up of line segments

Acute Angle

Acute Triangle

Angle

Area

An angle that measures less than 90 degrees.

A triangle for which all interior angles are acute.

Two rays sharing a common endpoint.

Base X Height

Acute Angle

An angle that measures less than 90 degrees.

Acute Triangle

A triangle for which all interior angles are acute.

adjacent angle

acute angle

angle bisector

angle

Two angles that share a common vertex and side, but have no c…

An angle that has a measure greater than 0⁰ and less than 90⁰

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that... have th…

adjacent angle

Two angles that share a common vertex and side, but have no c…

acute angle

An angle that has a measure greater than 0⁰ and less than 90⁰

adjacent angle

acute angle

angle bisector

angle

Two angles that share a common vertex and side, but have no c…

An angle that has a measure greater than 0⁰ and less than 90⁰

A ray that divides an angle into two angles that are congruent

A set of points consisting of two different rays that... have th…

adjacent angle

Two angles that share a common vertex and side, but have no c…

acute angle

An angle that has a measure greater than 0⁰ and less than 90⁰

angle

closed shape

line

line segment

a shape formed by two rays that share the same endpoint

a two-dimensional shape that begins and ends at the same poin…

a straight path extending in both directions with no endpoints

a part of a line that includes two endpoints and all the poin…

angle

a shape formed by two rays that share the same endpoint

closed shape

a two-dimensional shape that begins and ends at the same poin…

Circumference

Chord

Radius

Rectangle

The distance (perimeter) around a circle.

A straight line that goes from one edge of a circle to anothe…

A straight line between the center point of a circle and it's…

A quadrilateral with 4 right angles.

Circumference

The distance (perimeter) around a circle.

Chord

A straight line that goes from one edge of a circle to anothe…

area

perimeter

line

line segment

the measure in square units of the inside of a flat figure

the distance around the outside of a figure

a set of connected points continuing in both directions witho…

part of a line with two endpoints

area

the measure in square units of the inside of a flat figure

perimeter

the distance around the outside of a figure

Adjacent arcs

Center of a circle

Central angle of a circle

Chord of a circle

Arcs of a circle that have exactly one point in common

The point from which all points on a circle are equidistant

An angle whose vertex is the center of a circle

A segment whose endpoints are on a circle

Adjacent arcs

Arcs of a circle that have exactly one point in common

Center of a circle

The point from which all points on a circle are equidistant