Friday, July 4, 2008

Geometry 1st Qtr July 3, 2008

BASIC GEOMETRY
The Basic Postulate
Postulate #1 Midpoint Postulate
"every segment has exactly one midpoint"

Postulate #2 Points Postulate
A line contains infinite points

Postulate #3 Lines Postulate
For every two points there is exactly one line that contains both points

Postulate #4 Plane Postulate
Any 3 points lie in at least one plane
Any 3 non collinear points lie in exactly one plane

Postulate #5 Space Postulate
A space contains at least 4 non collinear points

Postulate #6 Flat Plane Postulate
If two points of a line lie in a plane, then the line lies in the same plane

Postulate #7 Plane Intersection Postulate
If two different planes intersect then their intersection is a line

Postulate #8 Distance Postulate
To every pair of different points there corresponds a unique positive real number

Definition:
The distance between two points is the number given by the Distance Postulate. If the points are P and Q, then the distance is demoted as PQ or QP

Postulate #9 The Ruler Postulate
The points of a line can be placed in correspondence with the real numbers such that to every...
> point of the line there corresponds exactly one real number
> number there corresponds exactly one point of the line; and the distance between any two points is the absolute value of the difference of the corresponding real number.
-> Any real number corresponding to a given point is called the coordinate of a point. The one to one correspondence between the point of a line and the set or real numbers is called a coordinate system

Postulate #10 The Ruler Placement Postulate
Given two points P and Q of a line, the coordinate system can be chosen such that the coordinate of P is zero and the coordinate of Q is positive

Postulate #11 Segment Construction Postulate
Let a RD be a ray, and let x be a positive number then there's exactly one point P of RP such that RP=x.

THEOREMS

2.1 Theorem Line Intersection Theorem
If two different lines intersect, their intersection contains only one point

2.2 Line-Plane Intersection Theorem
If a line intersects a plane not containing it, then the intersection contains only one point.

2.3 Point-Line Plane Theorem
Given a line and a point not on the line there is exactly one plane containing both

2.4 Intersecting Lines Planes Theorem
Given two intersecting lines, there is exactly one plane containing both

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