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Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A line or segment that divides a line segment into two equal…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A line or segment that divides a line segment into two equal…

Inductive reasoning

conjecture

postulate

deductive reasoning

the process of observing data, recognizing patterns, and maki…

A generalization resulting from inductive reasoning.

a statement accepted without proof, because it cannot be disp…

process of showing that certain statements follow logically f…

Inductive reasoning

the process of observing data, recognizing patterns, and maki…

conjecture

A generalization resulting from inductive reasoning.

Equiangular Polygon

Equilateral Polygon

Quadrilateral

Polygon

a polygon where all the angles have the same measure

a polygon where all the sides have the same measure

a polygon with four sides

a closed figure in a plane, formed by connecting line segment…

Equiangular Polygon

a polygon where all the angles have the same measure

Equilateral Polygon

a polygon where all the sides have the same measure

Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A line or segment that divides a line segment into two equal…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A line or segment that divides a line segment into two equal…

Equiangular Polygon

Equilateral Polygon

Quadrilateral

Polygon

a polygon where all the angles have the same measure

a polygon where all the sides have the same measure

a polygon with four sides

a closed figure in a plane, formed by connecting line segment…

Equiangular Polygon

a polygon where all the angles have the same measure

Equilateral Polygon

a polygon where all the sides have the same measure

counterexample

classify and differentiate

perpendicular

parallel

An example that shows a conjecture tone incorrect or a defini…

Defining a term by categorizing it, then distinguishing it fr…

Lines are perpendicular if they meet at 90 degree angles. Lin…

Lines are parallel if they lie in the same plane and do not i…

counterexample

An example that shows a conjecture tone incorrect or a defini…

classify and differentiate

Defining a term by categorizing it, then distinguishing it fr…

construct

sketch

draw

segment bisector

Making a shape through the use of a compass and straightedge.…

A free hand drawing

Making a shape through the use of your compass, straightedge,…

A line, ray, or segment that passes through the midpoint of a…

construct

Making a shape through the use of a compass and straightedge.…

sketch

A free hand drawing

Exterior Angle

Adjacent Interior Angle

Remote Interior Angles

Vertex angle

an angle outside of a polygon formed from an extension of a s…

angle next to an exterior angle

angles opposite the adjacent interior angle

The angle between the congruent legs of an isosceles triangle

Exterior Angle

an angle outside of a polygon formed from an extension of a s…

Adjacent Interior Angle

angle next to an exterior angle

Inductive reasoning

conjecture

postulate

deductive reasoning

the process of observing data, recognizing patterns, and maki…

A generalization resulting from inductive reasoning.

a statement accepted without proof, because it cannot be disp…

process of showing that certain statements follow logically f…

Inductive reasoning

the process of observing data, recognizing patterns, and maki…

conjecture

A generalization resulting from inductive reasoning.

Image

preimage

isometry

line of reflection

the result of moving a figure according to a transformation.

the original figure of a transformation

A transformation that preserves size and shape.

the line over which every point of a figure is moved by a ref…

Image

the result of moving a figure according to a transformation.

preimage

the original figure of a transformation

point

line

plane

definition

An undefined term thought of as a location with no size or di…

An undefined term thought of as a straight, continuous arrang…

An undefined term thought of as a flat surface that extends i…

A statement that clarifies or explains the meaning of a word…

point

An undefined term thought of as a location with no size or di…

line

An undefined term thought of as a straight, continuous arrang…

angle

vertex (of an angle)

side (of an angle)

measure of an angle

Two non collinear rays having a common endpoint.

The common endpoint of the two rays of the angle.

One of the two rays that form an angle.

The smallest amount of rotation about the vortex from one ray…

angle

Two non collinear rays having a common endpoint.

vertex (of an angle)

The common endpoint of the two rays of the angle.

concurrent lines

point of concurrency

circumcenter

orthocenter

Two or more lines that intersect in a single point.

The point at which two or more lines, line segments, or rays…

The point of concurrency of a triangle's three angle bisectors.

The point of concurrency of a triangle's three altitudes (or…

concurrent lines

Two or more lines that intersect in a single point.

point of concurrency

The point at which two or more lines, line segments, or rays…

circle

center (of a circle)

radius

chord

The set of all points in a plane at a given distance from a g…

The coplanar point from which all points of the circle are th…

A line segment from the center of a circle or sphere to a poi…

A line segment whose endpoints lie on a circle.

circle

The set of all points in a plane at a given distance from a g…

center (of a circle)

The coplanar point from which all points of the circle are th…

assume

right triangle

acute triangle

obtuse triangle

To accept as true without facts or proof.

A triangle with a right angle.

A triangle with three acute angles.

A triangle with an obtuse angle

assume

To accept as true without facts or proof.

right triangle

A triangle with a right angle.

polygon

side (of a polygon)

vertex (of a polygon)

angle (of a polygon)

A closed figure in a plane, formed by connecting line segment…

A line segment connecting consecutive vertices of a polygon.

An endpoint where two sides of the polygon meet.

An angle having two adjacent sides of the polygon as its sides.

polygon

A closed figure in a plane, formed by connecting line segment…

side (of a polygon)

A line segment connecting consecutive vertices of a polygon.

Rectangle Area Conjecture

Parallelogram Area Conjecture

Triangle Area Conjecture

Trapezoid Area Conjecture

The area of a rectangle is given by the formula A=bh, where A…

The area of a parallelogram is given by the formula A=bh, whe…

The area of a triangle is given by the formula A=1/2bh, where…

The area of a trapezoid is given by the formula A=1/2(b1+b2)h…

Rectangle Area Conjecture

The area of a rectangle is given by the formula A=bh, where A…

Parallelogram Area Conjecture

The area of a parallelogram is given by the formula A=bh, whe…

Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A line or segment that divides a line segment into two equal…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A line or segment that divides a line segment into two equal…

point

line

plane

collinear points

undefined - has no size, only a location, names with a capita…

undefined - straight, continuous arrangement of infinitely ma…

undefined - has length and width, but no thickness; like flat…

points that are on the same line

point

undefined - has no size, only a location, names with a capita…

line

undefined - straight, continuous arrangement of infinitely ma…

Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A segment that has many perpendiculars and many bisectors, bu…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A segment that has many perpendiculars and many bisectors, bu…

Base angles (of a trapezoid)

Exterior angle (of a polygon)

Isosceles trapezoid

Midsegment (of a trapezoid)

A pair of angles with a base of the trapezoid as a common side

An angle that forms a linear pair with one of the interior an…

A trapezoid whose two nonparallel sides are congruent

The line segment connecting the midpoints of the two nonparal…

Base angles (of a trapezoid)

A pair of angles with a base of the trapezoid as a common side

Exterior angle (of a polygon)

An angle that forms a linear pair with one of the interior an…

Equiangular Polygon

Equilateral Polygon

Quadrilateral

Polygon

a polygon where all the angles have the same measure (congrue…

a polygon where all the sides have the same measure

a polygon with four sides

a closed figure in a plane, formed by connecting line segment…

Equiangular Polygon

a polygon where all the angles have the same measure (congrue…

Equilateral Polygon

a polygon where all the sides have the same measure

Inscribed Circle

Circumscribed Circle

Concurrent Lines

Incenter

A circle that is inside a triangle and is tangent to its sides.

A circle that goes around a triangle and passes through its v…

Lines that meet at a common point.

The center of the inscribed circle of a triangle.

Inscribed Circle

A circle that is inside a triangle and is tangent to its sides.

Circumscribed Circle

A circle that goes around a triangle and passes through its v…

tessellation

monohedral tessellation

regular tessellation

vertex arrangement

A repeating pattern of shapes that completely cover a plane w…

A tessellation that uses only one shape.

A tessellation of congruent regular polygons

A notation that uses positive integers and other symbols to d…

tessellation

A repeating pattern of shapes that completely cover a plane w…

monohedral tessellation

A tessellation that uses only one shape.

n-gon

trapezoid

polygon

interior angle

A polygon with n sides.

A quadrilateral with exactly one pair of... parallel sides.

A closed figure in a plane, formed by connecting line segment…

An angle of a polygon that lies inside the polygon.

n-gon

A polygon with n sides.

trapezoid

A quadrilateral with exactly one pair of... parallel sides.

tangent segment

tangent circles

internally tangent circles

externally tangent circles

A line segment that lies on a tangent line with one endpoint…

Circles that are tangent to the same line at the same point.

Two tangent circles having centers on the same side of their…

Two tangent circles having centers on opposite sides of their…

tangent segment

A line segment that lies on a tangent line with one endpoint…

tangent circles

Circles that are tangent to the same line at the same point.

altitude of a triangle

median

midsegment

perpendicular bisector conjecture

distance from a vertex to the opposite side or the extension…

segment from a vertex to the midpoint of the opposite side of…

segment connecting two midpoints of the sides of a triangle

all points on the perpendicular bisector are equidistant from…

altitude of a triangle

distance from a vertex to the opposite side or the extension…

median

segment from a vertex to the midpoint of the opposite side of…

image

transformation

isometry

nonrigid transformation

The result of moving all points of a figure according to a tr…

A rule that assigns to each point of a figure another point i…

A transformation that preserves size and shape. The image of…

A transformation that does not preserve the size of the origi…

image

The result of moving all points of a figure according to a tr…

transformation

A rule that assigns to each point of a figure another point i…

Triangle Sum conjecture

Triangle Inequality

Side Angle Inequality

Exterior Angle conjecture

the angles of a triangle have a sum of 180 degrees

sum of two sides of a triangle must be greater than the third…

longest side of a triangle is opposite the largest angle

Triangle Sum conjecture

the angles of a triangle have a sum of 180 degrees

Triangle Inequality

sum of two sides of a triangle must be greater than the third…

polyhedron

face

edge

vertex (of a polyhedron)

A solid formed by polygonal surfaces that enclose a single re…

One of the polygons and its interior forming the surface of a…

The intersection of two faces in a polyhedron.

A point of intersection of three or more edges.

polyhedron

A solid formed by polygonal surfaces that enclose a single re…

face

One of the polygons and its interior forming the surface of a…

Triangle Sum Conjecture

Auxiliary line

Legs

Isosceles Triangle Conjecture

The sum of the measures of the angles in every triangle is 180°

An extra line or segment that helps with a proof

The other two sides of an isosceles triangle that are not the…

If a triangle is isosceles, then its base angles are congruent

Triangle Sum Conjecture

The sum of the measures of the angles in every triangle is 180°

Auxiliary line

An extra line or segment that helps with a proof

inductive reasoning

deductive reasoning

Overlapping Segments Conjecture

Overlapping Angles Conjecture

reasoning based on a pattern

reasoning based on logical argument

AC = BD

measure angle APD = measure angle CPD

inductive reasoning

reasoning based on a pattern

deductive reasoning

reasoning based on logical argument

Circumference

Cyclic quadrilateral

Externally tangent (circles)

Inscribed (in a circle, semicircle, or…

The distance around a circle, given by the formula C=2πr, whe…

A quadrilateral that can be inscribed in a circle

Intersecting at exactly the one point, with neither circle in…

Having each vertex on the circle, semicircle, or sphere. Usua…

Circumference

The distance around a circle, given by the formula C=2πr, whe…

Cyclic quadrilateral

A quadrilateral that can be inscribed in a circle

Tangent Conjecture

Tangent Segments Conjecture

Chord Central Angles Conjecture

Chord Arcs Conjecture

A tangent to a circle is perpendicular to the radius drawn to…

Tangent segments to a circle from a point outside the circle…

If two chords in a circle are congruent, then they determine…

If two chords in a circle are congruent, then their intercept…

Tangent Conjecture

A tangent to a circle is perpendicular to the radius drawn to…

Tangent Segments Conjecture

Tangent segments to a circle from a point outside the circle…

Linear Pair Conjecture

Vertical Angles Conjecture

Corresponding Angles Conjecture

Alternate Interior Angles Conjecture (…

If two angles form a linear pair then the measures of the ang…

If two angles are vertical angles, then they are congruent.

If two parallel lines are cut by a transversal then correspon…

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

Linear Pair Conjecture

If two angles form a linear pair then the measures of the ang…

Vertical Angles Conjecture

If two angles are vertical angles, then they are congruent.

Triangle Sum Conjecture

Auxiliary line

Legs of an Isosceles Triangle

Isosceles Triangle Conjecture

The sum of the measures of the angles in every triangle is 180°

An extra line or segment that helps with a proof

The two sides of an isosceles triangle that are not the base.

If a triangle is isosceles, then its base angles are congruent

Triangle Sum Conjecture

The sum of the measures of the angles in every triangle is 180°

Auxiliary line

An extra line or segment that helps with a proof

Rectangle Area Conjecture

Parallelogram Area Conjecture

Triangle Area Conjecture

Trapezoid Area Conjecture

The area of a rectangle is given by the formula A=bh, where A…

The area of a parallelogram is given by the formula A=bh, whe…

The area of a triangle is given by the formula A=1/2bh, where…

The area of a trapezoid is given by the formula A=1/2(b1+b2)h…

Rectangle Area Conjecture

The area of a rectangle is given by the formula A=bh, where A…

Parallelogram Area Conjecture

The area of a parallelogram is given by the formula A=bh, whe…

Equiangular Polygon

Equilateral Polygon

Quadrilateral

Polygon

a polygon where all the angles have the same measure (congrue…

a polygon where all the sides have the same measure

a polygon with four sides

a closed figure in a plane, formed by connecting line segment…

Equiangular Polygon

a polygon where all the angles have the same measure (congrue…

Equilateral Polygon

a polygon where all the sides have the same measure

point

line

plane

collinear

An undefined term thought of as a location

An undefined term thought of as a straight,... continuous arrang…

An undefined term thought of as a flat... surface that extends i…

This means on the same line

point

An undefined term thought of as a location

line

An undefined term thought of as a straight,... continuous arrang…

Distance (between two points)

Hypotenuse

Legs (of a right triangle)

Pythagorean Theorem

The length of the line segment between two points

The side opposite the right angle in a right triangle. The ot…

The two sides of a triangle that are not the hypotenuse

The theorem that says that, in a right triangle, the sum of t…

Distance (between two points)

The length of the line segment between two points

Hypotenuse

The side opposite the right angle in a right triangle. The ot…

Equiangular Polygon

Equilateral Polygon

Quadrilateral

Polygon

a polygon where all the angles have the same measure

a polygon where all the sides have the same measure

a polygon with four sides

a closed figure in a plane, formed by connecting line segment…

Equiangular Polygon

a polygon where all the angles have the same measure

Equilateral Polygon

a polygon where all the sides have the same measure

collinear points

coplanar points

midpoint of a segment

parallel lines

points that are on the same line

objects that are on the same plane

a point on a segment that is equidistant from its endpoints

two or more lines on the same plane that do not intersect

collinear points

points that are on the same line

coplanar points

objects that are on the same plane

Distance (between two points)

Hypotenuse

Legs (of a right triangle)

Pythagorean Theorem

The length of the line segment between two points

The side opposite the right angle in a right triangle. The ot…

The two sides of a triangle that are not the hypotenuse

The theorem that says that, in a right triangle, the sum of t…

Distance (between two points)

The length of the line segment between two points

Hypotenuse

The side opposite the right angle in a right triangle. The ot…

Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A segment that has many perpendiculars and many bisectors, bu…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A segment that has many perpendiculars and many bisectors, bu…

n-gon

trapezoid

polygon

interior angle

A polygon with n sides.

A quadrilateral with exactly one pair of... parallel sides.

A closed figure in a plane, formed by connecting line segment…

An angle of a polygon that lies inside the polygon.

n-gon

A polygon with n sides.

trapezoid

A quadrilateral with exactly one pair of... parallel sides.

Isosceles Trapezoid Conjecture

Isosceles Trapezoid Diagonals Conjecture

Three Midsegments Conjecture

Triangle Midsegment Conjecture

The base angles of an isosceles trapezoid are congruent.

The diagonals of an isosceles trapezoid are congruent.

The three midsegments of a triangle divide the triangle into…

A midsegment of a triangle is parallel to the third side and…

Isosceles Trapezoid Conjecture

The base angles of an isosceles trapezoid are congruent.

Isosceles Trapezoid Diagonals Conjecture

The diagonals of an isosceles trapezoid are congruent.