Structure and Reasoning in Geometry

Lesson: Euclidean Geometry

Vocabulary

Point existence postulate for lines: A line contains at least two points

Collinear: Points on the same line

Unique line postulate: through any two points there exists one and only one line

Point existence postulate for planes: a plane contains least three noncollinear planes

Unique plane postulate: through any three non collinear points there exists one and only one plane

Flat plane postulate: If two points are in a plane, then the line that contains those two points lies entirely in the plane

Words to know

Point:

no dimensions

is a location on a coordinate plane

designed by an ordered pair (x,y)

identified with a single capital letter

Line:

One-dimensional set of infinite points

has no beginning or end

identified with a lowercase italicized

letter or two capital letters representing two points on the line

Plane:

Two-dimensional set of all points

Flat or level surface has no beginning or end

identified with a capital italicized letter