In class examples: Chapter 2: lesson 4, examples 1-4
Vocabulary
A line is a line perpendicular to a plane if and only if the line intersects the plane in a point and is perpendicular to every line in the plane that intersects it at that point.
Postulate 5 Through any two points there exists exactly one line.
Postulate 6 A line contains at least two points.
Postulate 7 If two lines intersect, then their intersection is exactly one point.
Postulate 8 Through any three noncollinear points there exists exactly one plane.
Postulate 9 A plane contains at least three noncollinear points.
Postulate 10 If two points lie in a plane, then the line containing them lies in the plane.
Postulate 11 If two planes intersect, then their intersections is a line.
