Angles and Segments Review

Vocabulary flashcards reviewing concepts of angles, segments, geometric notation, and angle pairs.

Angle

A geometric figure created by two rays that share the same initial point or vertex.

Vertex

The point where two rays meet to create an angle.

Angle Naming Rules

Angles can be named using three letters where order matters (such as $\angle ABC$ or $\angle CBA$), or using a single letter for the vertex point (such as $\angle B$) only if no other angles share that same vertex point.

Point

A geometric concept represented by one capital letter.

Line Segment

A straight part of a line bounded by two endpoints, named using two letters such as $\overline{JK}$.

Line

A straight geometric path extending infinitely in opposite directions, named using two or three letters such as $\overleftrightarrow{SR}$.

Ray

A portion of a line with one endpoint that extends infinitely in one direction, named using two letters where order matters such as $\overrightarrow{QS}$.

Complementary Angles

Any two angles whose sum is $90^\circ$ ($\text{part} + \text{part} = 90^\circ$).

Supplementary Angles

Any two angles whose sum is $180^\circ$ ($\text{part} + \text{part} = 180^\circ$).

Vertical Angles

Two angles across from each other on intersecting lines that are always congruent ($\cong$).

Adjacent Angles

Angles next to one another that share a common ray and vertex.

Linear Pair

Two angles that are adjacent and supplementary, forming a straight line ($\text{part} + \text{part} = \text{whole } (180^\circ)$).

Midpoint

A point on a line segment that divides it into two congruent parts, resulting in $\overline{AM} \cong \overline{BM}$.