Vocab Flashcards
Inductive reasoning
Looking for patterns and making conjectures.
Conjecture
An unproven statement based on observations.
Counter example
An example that shows a conjecture false.
Point
No dimensions, represented by a small dot
Line
Straight line with 2 arrowheads to show the line extends in both directions without end.
Plane
Extends in 2 directions without end. Represented by a shape like a tabletop or a wall
Collinear
Points that lie on the same line.
Coplanar
Points that lie on the same plane.
Segment
Consist of end points A&B and all points in between.
Endpoints
Points at the end.
Ray
Consists of an initial point A and all points AB that lie on the side of A as B.
Initial point
If C between A&B, then CA and CB are opposite rays.
Intersect
2 or more geometric figures intersect if they have one or more points in common.
Intersection
The set of all points the figures have in common.
Postulate or axiom
Rules that are accepted without any proof.
Congruent segments
Segments that have the same length.
Ruler Postulate
The points on a line can be matched with real numbers. The real number that corresponds to a point is a coordinate. The distance between points A&B written as AB is the absolute value of the difference between A&B.
Segment Addition Postulate
If B is between A and C, then AB+BC=AC. If AB+BC=AC, then B is between A and C.
Angle
2 different rays with the same initial point.
Sides
The rays are the sides of the angle.
Vertex
The initial point is the vertex of the angle
Congruent angles
Angles that have the same measure.
Interior
A point is in the interior of an angle if it is between that lie on each side of the angle.
Exterior
A point on the outside if it is not on the interior on the angle itself.
Acute
Angle that measures >0 degrees and < 90 degrees.
Right angle
Angle measures exactly 90 degrees.
Obtuse angle
Angle measure >90 degrees but <180 degrees.
Straight angle
Measures at exactly 180 degrees.
Adjacent angles
2 angles are next to each other if they share a common vertex and side but have no common interior points.
Protractor postulate
Measure of <AOC is the absolute value of the difference between the real numbers for OA and OC.
Angle Addition Postulate
If P is in the interior of <RST.