Geometry Vocabulary
Chapter 1
Segment: or line segment is part of a line consisting of two points and all points between them.
Endpoint: point at one end of segment or starting point of ray.
Ray: part of line that starts at endpoint and extends forever in one direction.
Opposite rays: two rays have common endpoint and form line.
Collinear: points lie on same line.
Coplanar: points lie in same plane.
Postulate: accepted true without proof:
Construction: creating figure more precise.
Midpoint is point that bisects or divides segment into two congruent segments.
Segment Bisector: any ray, segment, or line that intersects segment at endpoint.
Angle Bisector: a ray that divides angles into two congruent angles.
Adjacent Angles: two angles in same plane with common vertex and common side but no common interior points.(meaning side by side)
Linear Pair: pair of adjacent angles whose noncommon sides are opposite rays. (form 180 degrees)
Vertical Angles: two nonadjacent anles formed byt two intersecting lines.
Area of Triangle: 1/2bh Area of Circle: pi r squared cir: pi d or 2 pi r
Legs: sides that form right angle.
Hypotenuse: side across from right angle that stretches from one leg to the other.(longest side)
Reflection or flip- Rotation or turn- Translation or slide
Chapter 2
Biconditional Statement: statement that can be written in form “p if and only if q”
Conclusion: Conditional statement following the word then.
Conditional Statement: statement that can be written in form “if p, then q”,where p is hypothesis and q is conclusion.
Conjecture: statement believed to be true.
Contrapositive: statement formed by both exchanging and negating the hypothesis and conclusion of a conditional statement.
Converse: statement formed by exchanging the hypothesis and conclusion of a conditional statement.
Counterexample: example that proves a conjecture or statement is false.
Deductive Reasoning: the process of using logic to draw conclusions.
Definition: a statement that describes a mathematical object and can be written as a true biconditional statement.
Flowchart Proof: a style of proof that uses boxes and arrows to show the structure of the proof.
Hypothesis: The part of a conditional statement following the word if.
Inductive Reasoning: the