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Geometry Vocab - Points, Lines, Angles, & Polygons
A location represented by a dot
An infinate set of points extending endlessly in both directions
Set of points that form a flat surface that extends infinitely in both directions
Points that are on the same line
Points that are not on the same line
B is between A and C if and only if A, B, C are distinct collinear points and AB + BC = AC
Points that are on the same plane
2 lines that never intersect (in same plane)
2 lines that intersect to form right angles (in same plane)
Set of points consisting of two points on a line, called endpoints , and all points on the line between the endpoints
Length/Measure of a Segment
Distance between its endpoints
Segments that have the same length/measure
Point on a segment that divides the segments into 2 congruent segments
Bisector of a Segment
Line, ray or a segment that intersects a segment at its midpoint
Part of a line consisting of an endpoint and extending infinitely in the other direction
2 rays of the SAME LINE with a common endpoint.
The union of 2 rays having the same endpoint (vertex)
A 180 degree angle (line)
Between 0 degrees and 90 degrees
A 90 degree angle
between 90 degrees and 180 degrees
Two angles that have the same measure
Ray whose endpoint is the vertex of the angle and it divides the angle into 2 congruent angles
A pair of angles, the sum of whose degree measures 90 degrees
A pair of angles, the sum of whose degree measures 180
2 adjacent angles whose sum is a straight angle
Angles formed across from one another and are congruent
Two angles who share a common vertex, common side (ray), but no common interior points
A closed figure in a plane that is the union of line segments such that the segments only intersect at their endpoints and no segments sharing a common endpoint are collinear.
A polygon that has exactly 3 sides
Triangle that has exactly had no cogruent sides
Triangle that has 2 congruent sides
Triangle that has 3 congruent sides
Triangle that has 3 acute angles
Triangle that has 3 congruent angles
Triangle that has a right angle
Triangle that has an obtuse angle
Lines in the same plane that have no points in common OR all points in common.
(height) Line segment drawn from a vertex to the opposite side and is perpendicular to it.
Line segment drawn from a vertex to the midpoint of the opposite side.