13DegreeA unit of measure used in measuring angles and arcs. An arc of a circle with a measure of 1degree is 1/ 360 of the entire circle.
14ExteriorA point is in the exterior of an angle if it is neither on the angle nor in the interior of the angle.
15InteriorA point is in the interior of an angle if it does not lie on the angle itself and it lies on a segment with endpoints that are on the sides of the angle.
16LineA basic undefined term of geometry. It is made up of points and has no thickness or width. In a figure, it is shown with an arrowhead at each end. Usually named by lowercase script letters or by writing the capital letters for two endpoints, with a double arrow over the pair of letters.
17Line SegmentA measureable part of a line that consists of two points, called endpoints, and all of the points between them.
18Linear PairA pair of adjacent angles whose non-common sides are opposite rays.
19LocusThe set of points that satisfy a given condition.
20MidpointThe point halfway between the endpoints of a segment.
26PlaneA basic undefined term in geometry. It is a flat surface made up of points that has no depth and extends indefinitely in all directions. In a figure, it is often represented by a shaded, slanted 4-sided figure. Usually named by a capital script letter or by three non collinear points.
27PointA basic undefined term in geometry. It is a location. In a figure, it is usually represented by a dot and named by a capital letter.
28PolygonA closed figure formed by a finite number of coplanar segments called sides such that the following conditions are met:The sides that have a common endpoint are noncollinear.Each side intersects exactly two other sides, but only at their endpoints, called vertices.
29PrecisionDepends on the smallest unit available on the measurement tool.
30RayA part of a line. It has one endpoint and extends indefinitely in one direction.
31Regular PolygonA convex polygon in which all of the sides are congruent and all of the angles are congruent.
32Relative ErrorThe ratio of the half-unit difference in precision to the entire measure, expressed as a percent.
33Right AngleAn angle with a degree measure of 90.
34Segment BisectorA segment, line, or plane that intersects a segment at its midpoint.