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congruent figures

congruence transformation

dilation

center of dilation

Geometric figures that have the same size and shape

A transformation that preserves length and angle measure

A transformation in which a figure is enlarged or reduced wit…

The fixed point in a dilation

congruent figures

Geometric figures that have the same size and shape

congruence transformation

A transformation that preserves length and angle measure

triangle

vertex

adjacent sides

legs of a right triangle

a figure formed by three segments joining three noncollinear…

one of the three points joining the sides of a triangle

two sides sharing a common vertex in a triangle

in a right triangle, the sides that form the right angle

triangle

a figure formed by three segments joining three noncollinear…

vertex

one of the three points joining the sides of a triangle

acute triangle

auxiliary line

base

dilation

A triangle that contains only angles that are less than 90 de…

a line drawn in a figure to aid in a proof

bass of a triangle

a transformation in which the lines connecting every point P…

acute triangle

A triangle that contains only angles that are less than 90 de…

auxiliary line

a line drawn in a figure to aid in a proof

Angle of rotation

Center of rotation

Center of symmetry

Component form

The angle that is formed by rays drawn from the center of rot…

The fixed point in a rotation.

The center of rotation in a figure that has rotational symmet…

A form of a vector that combines the horizontal and vertical…

Angle of rotation

The angle that is formed by rays drawn from the center of rot…

Center of rotation

The fixed point in a rotation.

point

line

line segment

plane

a location in space

a straight path of points that goes on endlessly in both dire…

a part of a line having 2 endpoints

a flat surface that goes on endlessly in all directions

point

a location in space

line

a straight path of points that goes on endlessly in both dire…

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

acute triangle

auxiliary line

base

base angle

a triangle whose interior angles are all acute

a line that is added to a figure in a proof

the side opposite the vertex angle

an angle that has the base as a side with another angle

acute triangle

a triangle whose interior angles are all acute

auxiliary line

a line that is added to a figure in a proof

Side-Side-Side Congruence Postulate (S…

Angle-Side-Angle Congruence Theorem (A…

Side-Angle-Side Congruence Postulate (…

Side-Side-Angle Conjecture (SSA)

If the sides of one triangle are congruent to the sides of an…

If two angles and the included side in one triangle are congr…

If two sides and their included angle in one triangle are con…

In an SSA combination, if the given side opposite the given a…

Side-Side-Side Congruence Postulate (S…

If the sides of one triangle are congruent to the sides of an…

Angle-Side-Angle Congruence Theorem (A…

If two angles and the included side in one triangle are congr…

Congruent Polygons

Triangle Congruence by SSS

Triangle Congruence by SAS

Triangle Congruence by ASA

Have congruent corresponding (matching) sides and correspondi…

If three sides of one triangle are congruent to the three sid…

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

If two angles and the included side of one triangle are congr…

Congruent Polygons

Have congruent corresponding (matching) sides and correspondi…

Triangle Congruence by SSS

If three sides of one triangle are congruent to the three sid…

Triangle Sum Theorem

Definition: Triangle Exterior Angle

Remote Interior Angles

Triangle Exterior Angle Theorem

The sum of the interior angles of a triangle is 180 degrees.

The angle formed by one side of a polygon and the extension o…

The two angles in a triangle that are not adjacent to the ind…

The measure of the exterior angle of a triangle is equal to t…

Triangle Sum Theorem

The sum of the interior angles of a triangle is 180 degrees.

Definition: Triangle Exterior Angle

The angle formed by one side of a polygon and the extension o…

Angle of rotation

Center of rotation

Center of symmetry

Component form

The angle that is formed by rays drawn from the center of rot…

The fixed point in a rotation.

The center of rotation in a figure that has rotational symmet…

A form of a vector that combines the horizontal and vertical…

Angle of rotation

The angle that is formed by rays drawn from the center of rot…

Center of rotation

The fixed point in a rotation.

polygon

triangle

vertices

acute triangle

A figure in a plane made up of segments that are connected wi…

A polygon with three sides

The common endpoints in a triangle

All three angles are acute

polygon

A figure in a plane made up of segments that are connected wi…

triangle

A polygon with three sides

Acute Angle

Auxillary Line

Base Angles of Isosceles Triangle

Congruence Transformation

A triangle with 3 acute triangles

An extra line or segment drawn in a figure to help analyze ge…

The two angles formed by the base and the congruent sides

Rigid transformation or Isometry: the position of the image m…

Acute Angle

A triangle with 3 acute triangles

Auxillary Line

An extra line or segment drawn in a figure to help analyze ge…

triangle

equilateral triangle

isosceles triangle

scalene triangle

a figure formed by three segments joining three noncollinear…

a triangle with three congruent sides

a triangle with two congruent sides

a triangle with no congruent sides

triangle

a figure formed by three segments joining three noncollinear…

equilateral triangle

a triangle with three congruent sides

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

Triangle Sum Theorem

Exterior Angle Theorem

Side side side Congruence Postulate

side angle side congruence postulate

The sum of the angle measures of a triangle is 180.

The measure of an exterior angle of a triangle is equal to th…

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

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

Triangle Sum Theorem

The sum of the angle measures of a triangle is 180.

Exterior Angle Theorem

The measure of an exterior angle of a triangle is equal to th…

Acute Triangle

Equiangular Triangle

Obtuse Triangle

Right Triangle

A triangle that has 3 acute angles.

A triangle with 3 congruent acute angles.

A triangle that has 1 obtuse angle.

A triangle that has 1 right angle.

Acute Triangle

A triangle that has 3 acute angles.

Equiangular Triangle

A triangle with 3 congruent acute angles.

The two congruent angles of an isoscel…

The noncongruent side of an isosceles…

Polygons that have congruent correspon…

If you know two triangles are congruen…

Base Angles of Isosceles Triangle

Base of Isosceles Triangle

Congruent Polygons

Corresponding Parts of Congruent Triangles

The two congruent angles of an isoscel…

Base Angles of Isosceles Triangle

The noncongruent side of an isosceles…

Base of Isosceles Triangle

Polygon Congruence Postulate

SSS Congruence Postulate

SAS Congruence Postulate

ASA Congruence Postulate

Two polygons are congruent if and only if... 1. the correspondin…

Polygon Congruence Postulate

Two polygons are congruent if and only if... 1. the correspondin…

SSS Congruence Postulate

Base Angles of Isosceles Triangle

Base of an Isosceles Triangle

Congruent Polygons

Hypotenuse

Angles opposite the two congruent sides of an isosceles trian…

Side opposite the vertex angle of a isosceles triangle.

Has corresponding (matching sides and angles) congruent parts.

Side opposite the right angle of a triangle.

Base Angles of Isosceles Triangle

Angles opposite the two congruent sides of an isosceles trian…

Base of an Isosceles Triangle

Side opposite the vertex angle of a isosceles triangle.

3 Angle Classification of Triangles

3 Side Classifications of Triangles

Triangle Angle Sum Theorem

Exterior Angle Theorem

Acute: 3 Acute Angles ... Right: 1 right Angle ... Obtuse: 1 obtuse…

Equilateral: All sides equal ... Isosceles: At least 2 sides con…

Sum of Measures of angles of triangle are 180

Measure of exterior angle of triangle is equal to sum of meas…

3 Angle Classification of Triangles

Acute: 3 Acute Angles ... Right: 1 right Angle ... Obtuse: 1 obtuse…

3 Side Classifications of Triangles

Equilateral: All sides equal ... Isosceles: At least 2 sides con…

Angle of rotation

Center of rotation

Center of symmetry

Composition of transformations

The angle that is formed by rays drawn from the center of rot…

The fixed point in a rotation.

The center of rotation in a figure that has rotational symmet…

The combination of two or more transformations to form a sing…

Angle of rotation

The angle that is formed by rays drawn from the center of rot…

Center of rotation

The fixed point in a rotation.

acute triangle

auxiliary line

base of a triangle

base angle of an isosceles triangle

a triangle with 3 acute angles

a line drawn in a figure to aid in a proof

any side of a triangle

one of the two angles that have the base of the triangle as a…

acute triangle

a triangle with 3 acute angles

auxiliary line

a line drawn in a figure to aid in a proof

coordinate plane

parallelogram

quadrilateral

rhombus

a plane formed by the intersection of a horizontal number lin…

a quadrilateral with two pairs of parallel sides

a four-sided polygon

a parallelogram with all sides congruent

coordinate plane

a plane formed by the intersection of a horizontal number lin…

parallelogram

a quadrilateral with two pairs of parallel sides

detour proofs

midpoint formula

If two angles are both supplementary a…

distance

proof that requires more than one pair of triangles proven co…

then they are right angles.

the length of the shortest path joining two objects

detour proofs

proof that requires more than one pair of triangles proven co…

midpoint formula

Center of dilation

Congruence transformation

Congruent figures

Dilation

The fixed point in a dilation.

A transformation that preserves length and angle measure.... Tr…

Geometric figures that have the same size and shape.

A transformation in which a figure is enlarged or reduced wit…

Center of dilation

The fixed point in a dilation.

Congruence transformation

A transformation that preserves length and angle measure.... Tr…

Side-Side-Side Congruence Postulate (S…

Angle-Side-Angle Congruence Theorem (A…

Side-Angle-Side Congruence Postulate (…

Side-Side-Angle Conjecture (SSA)

If the sides of one triangle are congruent to the sides of an…

If two angles and the included side in one triangle are congr…

If two sides and their included angle in one triangle are con…

In an SSA combination, if the given side opposite the given a…

Side-Side-Side Congruence Postulate (S…

If the sides of one triangle are congruent to the sides of an…

Angle-Side-Angle Congruence Theorem (A…

If two angles and the included side in one triangle are congr…

Base Angles of an Isosceles Triangle

Base of an Isosceles Triangle

Congruent Polygons

Corollary

If two sides of a triangle are congruent (legs), then the ang…

The third side of the triangle that is not the legs (opposite…

Congruent corresponding parts- their matching sides and angles

a theorem that can be proved easily using another theorem; us…

Base Angles of an Isosceles Triangle

If two sides of a triangle are congruent (legs), then the ang…

Base of an Isosceles Triangle

The third side of the triangle that is not the legs (opposite…

attribute

center

circle

circumference

a characteristic of a figure

the point from which all points on a circle are the same dist…

the set of all points in a plane that are the same distance f…

the distance around a circle

attribute

a characteristic of a figure

center

the point from which all points on a circle are the same dist…

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

Right Angle

Acute Angle

Obtuse Angle

Acute Triangle

An angle that measures 90 degrees.

An angle that measures between 0 and 90 degrees.

An angle that measures between 90 and 180 degrees.

A triangle with three angles less than 90 degrees each.

Right Angle

An angle that measures 90 degrees.

Acute Angle

An angle that measures between 0 and 90 degrees.

Distance formula

Polygon

ASA postulate

SAS Postulate

Many sided figure made of at least 3 line segments

If 2 angles and the included side of one triangle are equal t…

If 2 sides and the included angle of one triangle are equal t…

Distance formula

Polygon

Many sided figure made of at least 3 line segments

Variable

Expression

Commutative Property

Associative Property

- usually a letter, used to represent an unknown or changing…

- a mathematical sentence that does not contain an equal sign.

- you can +/x numbers in any order. "Turn Around" (Ex: 5 + 7…

- when you +/x you can group numbers as you like, without cha…

Variable

- usually a letter, used to represent an unknown or changing…

Expression

- a mathematical sentence that does not contain an equal sign.

Divide

Dividend

Divisor

Factor

to separate into equal groups

the number that is to be divided in a division problem

the number that divdies the dividend

a number that is multiplied by another number to find a product

Divide

to separate into equal groups

Dividend

the number that is to be divided in a division problem

auxiliary line

paragraph proof

Triangle Sum Conjecture

leg

An extra line or line segment drawn in a figure to help in a…

A logical explanation presented in the form of a paragraph.

The sum of the measures of the angles in every triangle is 18…

(of an isosceles triangle) One of the congruent sides of an i…

auxiliary line

An extra line or line segment drawn in a figure to help in a…

paragraph proof

A logical explanation presented in the form of a paragraph.

auxiliary line

base angles

corollary

equilateral triangle

An extra line drawn to help analyze a figure.

Two angles formed by the base of an isosceles triangle and th…

A baby proof. Theorem with a proof that follows as a direct r…

All three sides equal.

auxiliary line

An extra line drawn to help analyze a figure.

base angles

Two angles formed by the base of an isosceles triangle and th…

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

alternate exterior angles

exterior angles

line

corresponding angles

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

Angles outside a polygon

A basic undefined term of geometry. Lines extend indefinitely…

Angles formed by a transversal cutting through 2 or more line…

alternate exterior angles

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

exterior angles

Angles outside a polygon

Angle of rotation

Center of rotation

Center of symmetry

Component form

The angle that is formed by rays drawn from the center of rot…

The fixed point in a rotation.

The center of rotation in a figure that has rotational symmet…

A form of a vector that combines the horizontal and vertical…

Angle of rotation

The angle that is formed by rays drawn from the center of rot…

Center of rotation

The fixed point in a rotation.