1-5 Postulates and Theorems Relating Points, Lines and Planes

Postulate A line contains at least two points, a plane contains at least 3 points not all in one line; space contains at least four points not all in one plane.

Postulate Through any two points there is exactly one line.

Postulate Through any 3 points there is at least one plane, and through any three noncollinear points there is EXACTLY one plane.

Postulate If two points are in a plane, then the line that contains the points is in the plane.

Postulate If two planes intersect, then their intersection is a line.

A line contains at least two points, a plane contains at least 3 points not all in one line; space contains at least for points not all in one plane. Through any two points there is exactly one line. Through any 3 points there is at least one plane, and through any three noncollinear points there is EXACTLY one plane. If two points are in a plane, then the line that contains the points is in the plane. If two planes intersect, then their intersection is a line.

What is a theorem? Important statements that have been PROVEN TRUE. From previous information

Theorem If 2 lines intersect, then they intersect in exactly one point.

Theorem Through a line and a point not in the line there is exactly one plane.

Theorem If 2 lines intersect, then exactly one plane contains the lines.

Homework Pg. 25 #s 5-17, 20 Pg. 30 #s 5-20