19 terms

# 9th Grade Honors Geometry MidTerms Study Guide

Contains all definitions, properties, postulates, theorems, and corollaries in Units 1, 2, 3, 4, 5, and 6.
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Space
The set of all points.
Collinear Points
Points all in one line.
Coplanar Points
Points all in one plane.
Intersection (of 2 Figures)
The set of points that are in both figures.
Line Segment
A part of a line that is bounded by two endpoints, and contains every point on the line between its endpoints.
Ray
A part of a line which is finite in one direction, but infinite in the other.
Opposite Rays
Ray SR and ray ST are called ________ ____ if S is between R and T.
Postulate
An assumption used as a basis for mathematical reasoning; axiom
Ruler Postulate (Postulate 1)
1) The points on a line can be paired with the real numbers in such a way that any two points can have the coordinates 0 and 1. 2) Once a coordinate system has been chosen in this way, the distance between any two points equals the absolute value of the difference of their coordinates.
If B is between A and C, then AB + BC = AC.
Congruent
In geometry, two objects that have the same size and shape are called _________.
Midpoint
The ________ of a segment is the point that divides the segment into two congruent segments.
Bisector
A ________ of a segment is a line, segment, ray, or plane that intersects the segment at its midpoint.
Angle (∠)
An _____ is the figure formed by two rays that have the same endpoint.
Acute Angle
An angle with a measure that is between 0 and 90.
Right Angle
An angle with a measure that is equal to 90.
Obtuse Angle
An angle with a measure that is between 90 and 180.
Straight Anglw
An angle with a measure that is equal to 180.
Protractor Postulate (Postulate 3)
On line AB in a given plane, choose any point O between A and B. Consider ray OA and ray OB and all the rays that can be drawn from O on one side of line AB. These rays can be paired with the reals numbers from 0 to 180 in such a way that: a) Ray OA is paired with 0, and ray OB with 180. b) If ray OP is paired with x, and ray OW with y, then m∠POQ = |x-y|.