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Basic Geometry Terms Flashcards

Basic Geometry Terms

Terms : Hide Images
1740561309PointA point has no size.0
1740561310LineGoes on forever in both directions. Two points create a line.1
1741609981PlaneA flat surface that has no thickness. Three points create a plane.2
1741609982CollinearPoints that lie on the same line. Points E, F, & C are collinear.3
1741609984Non-collinearPoints that do not lie on the same line. Points E, F, & D are non-collinear.4
1741609983CoplanarPoints and/or lines in the same plane. E, F, A, & B are coplanar points.5
1741637033Intersection of Two LinesIf two lines intersect, it is at exactly one point. Point C is the intersection of the two lines.6
1741637034Intersection of Two PlanesIf two planes intersect, then they intersect in exactly one line.7
1741637035Line SegmentThe part of a line consisting of two endpoints and all the points between them.8
1741637036RayThe part of a line consisting of one endpoint and all the points of the line on side of the endpoint.9
1741637037Opposite RaysTwo collinear rays with the same endpoint. Two opposite rays form a line.10
1741644306Parallel LinesCoplanar lines that do not intersect.11
1741644307Skew LinesNon-coplanar lines that do not intersect. Skew lines are NOT parallel.12
1741724843AngleFormed by two rays with the same endpoint.13
1741724844MidpointThe point that divides the segment into two congruent segments.14
1741724856CongruentHaving equal measure.15
1741724845Perpendicular LinesLines that intersect and form right angles.16
1741724846Acute AngleAn angle whose measure is between 0 and 90 degrees.17
1741724847Right AngleAn angle that measures 90 degrees.18
1741724848Obtuse AngleAn angle whose measure is between 90 and 180 degrees.19
1741724849Straight AngleAn angle that measures 180 degrees.20
1741724850Complementary AnglesTwo angles are complementary if the sum of their measures is 90 degrees.21
1741724851Supplementary AnglesTwo angles are supplementary is the sum of their measures is 180 degrees.22
1741724852Adjacent AnglesTwo coplanar angles that have a common side and a common vertex, but no common interior points.23
1741724853Linear PairTwo adjacent, supplementary angles.24
1741724854Vertical AnglesTwo angles whose sides form two pairs of opposite rays.25
1741724855Angle BisectorA ray that divides an angle into two congruent angles.26

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