Adjacent anglesTwo angles are Adjacent when they have a common side and a common vertex (corner point) and don't overlap.Angle Bisectortwo segments that a triangle's side is divided into by a line that bisects the opposite anglecollinearlying in the same straight line.complementary angleseither of two angles whose sum is 90°congruentTwo line segments are congruent if they have the same lengthlinear pairTwo angles are said to be linear if they are adjacent angles formed by two intersecting lines. The measure of a straight angle is 180 degreesopposite raysopposite rays are two rays that have the same endpoint and extend in opposite directionspolyhedrona solid figure with many plane facessegment bisectorA point, segment, line, or plane that divides a line segment into two equal partssupplementary angleseither of two angles whose sum is 180°vertical angleseach of the pairs of opposite angles made by two intersecting linesConditional statementan if-then statement in which p is a hypothesis and q is a conclusion. The logical connector in a conditional statement is denoted by the symbol . The conditional is defined to be true unless a true hypothesis leads to a false conclusion.Conclusiona judgment or decision reached by reasoningConjecturean opinion or conclusion formed on the basis of incomplete informationConverseOppositeCounterexampleA counterexample is a special kind of example that disproves a statement or propositionHypothesisa supposition or proposed explanation made on the basis of limited evidence as a starting pointPostulate 2.1Through any two points, there is exactly one linePostulate 2.2Through any three points not on the same line, there is exactly one plane
