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Quadrilateral

Trapezoid

Parallelogram

Rectangle

You are a flat shape with four straight sides. I am the most o…

you are a four sided figure with one pair of parallel sides.

You are a 4-sided flat shape with straight sides where opposit…

You are a 4-sided flat shape with straight sides where all int…

Geometry

Euclidean Geometry

Undefined terms

Point

word composed of two Greek terms, "geos" meaning earth and "me…

identifies a geometry which Euclid formalized and which was ad…

terms in Euclidean geometry which mathematicians consider only…

one of the undefined terms; it has only position and has no le…

Alternate Interior Angles

Consecutive Interior Angles

Alternate Exterior Angles

Corresponding Angles

Located on the interior of the lines, on opposite sides of the…

Located on the interior of the lines, on the same side of the…

Located on the exterior of the lines, on opposite sides of the…

Located on the interior and exterior of the lines, on the same…

they are congruent.... Right Angles Congr…

they are congruent.... Congruent Suppleme…

they are congruent.... Congruent Suppleme…

they are congruent.... Congruent Compleme…

If two angles are right angles, then

If two angles are supplementary to the same angle, then

If two angles are supplementary to congruent angles, then

If two angles are complementary to the same angle, then

Inductive Reasoning

Conjecture

Counter Example

Conditional Statement

The process of reasoning that a rule or statement is true beca…

A statement that is believed to be true

An example that proves a conjecture or statement false

A statement that can be written in the form "if p then q" wher…

corresponding angles

supplementary angles

adjacent angles

complimentary angles

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

Two or more angles whose sum is 180 degrees

Angles that have a common side and a common vertex (corner poi…

Two angles whose sum is 90 degrees

adjacent angle

acute angle

angle bisector

angle

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

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 the…

undefined terms

point

line

plane

in geometry point, line, and plane are considered undefined te…

is a location, it has neither shape nor size. Named by a capit…

made up of points and has no thickness or width. There is exac…

a flat surface made up of points that extends infinitely in al…

congruent figures

corresponding parts

Side-Side-Side Congruence Postulate (SSS)

Side-Angle-Side Congruence Postulate (S…

figures that have equal sides and equal angle measures

Figures or sides or angles that have the same relative position

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

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

midsegment of a triangle

coordinate proof

perpendicular bisector

equidistant

a segment that connects the midpoints of two sides of a triang…

a proof that uses figures in the coordinate plane and algebra…

A line that is perpendicular to a segment at its midpoint.

the same distance apart at every point

Nets for Three-Dimensional Figures

Arc Length

Area of a Circle

Area of a Sector

A two-dimensional pattern that can be folded to form the three…

The ratio of the length of a given arc to the circumference is…

A = πr²

The ratio of the area of a sector of a circle to the area of t…

adjacent angle

acute angle

angle bisector

angle

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

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 the…

Converse

Corresponding Angle Converse Postulate

Alternate Exterior Angle Converse Theorem

Alternate Interior Angle Converse Theorem

To state the converse of a conditional statement, interchange…

"If two lines intersected by a transversal form congruent corr…

"If two lines intersected by a transversal form congruent alte…

"If two lines intersected by a transversal form congruent alte…

Converse

Corresponding Angle Converse Postulate

Alternate Exterior Angle Converse Theorem

Alternate Interior Angle Converse Theorem

To state the converse of a conditional statement, interchange…

"If two lines intersected by a transversal form congruent corr…

"If two lines intersected by a transversal form congruent alte…

"If two lines intersected by a transversal form congruent alte…

point (what does it look like, how is i…

line (what does it look like, how is it…

plane (what does it look like, how is i…

acute angle

a dot; named with a capitalized letter

made up of points with no thickness or width; named by 2 capit…

flat surface made up of points; named by 3 three noncollinear…

an angle that measures less than 90 degrees