25 Geometry Terms

plane

a flat surface made of points

linear pair

a pair of adjacent angles whose non common sides are opposite rays

Angle Bisector

a ray that divides an angle into two congruent angles

segment bisector

a segment, line, or plane that intersects a segment at its midpoint

polyedron

a solid with all flat surfaces that enclose a single region of space.

degree

a unit of measure used in measuring angles and arcs

regular polygon

all sides are equal, all angles are equal. CONVEX ONLY

line segment

can be measured because it has two endpoints

polygon

closed figure, sides are all segments can be concave orconvex

angle

formed by two non colinear rays that have a common endpoint

congruent

having the same measure

perpendicular

lines that form right angles

line

made up of points has no thickness or width

Concave Polygon

no diagonals outside the figure

Concave Polygon

one or more diagonals outside the figure

ray

part of a line

undefined term

point, line and plane. (only been defined using examples and descriptions)

coplanar

points that lie on the same plane

vertex

the common endpoint

midpoint

the point halfway between the endpoints of a sement

Perimeter

the sum of all the sides of a polygon

adjacent angles

two angles that have a common vertex, lie on the same plane, and have a common side but no interior points

supplementary angles

two angles whose measures have a sum of 180

complementary angles

two angles whose measures have a sum of 90

vertical angles

two non adjacent angels formed by two intersecting lines