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1.2 Points, Lines, and Planes

- Chapter 1 Tools of Geometry

1.2 Points, Lines, and Planes

- Point a location has no size represented by a

small dot and is named by a capital letter - Space set of all points

Line series of points that extends to two

opposite directions Collinear Points points

that lie on the same line

- Are points E, F, and C collinear?
- If so, name the line on which they lie.
- Are points E, F, and D collinear?
- If so, name the line on which they lie.
- Are points F, P, and C collinear?
- If so, name the line on which they lie.
- Name line m in three other ways.

n

C

F

E

m

P

D

l

- Plane Flat surface that has no thickness

contains many points and lines named by a single

capital letter or at least three of its

noncollinear points - Coplanar points and lines in the same plane

- Each surface of the ice cube represents part of a

plane. Name the plane represented by the front

of the ice cube.

H

G

E

F

D

C

A

B

List three different names for the top of the ice

cube.

- Postulate or axiom accepted statement of fact
- Postulate 1-1
- Through any two points there is exactly one

line - Postulate 1-2
- If two lines intersect, then they intersect in

exactly one point.

B

A

- Postulate 1-3
- If two planes intersect, then they intersect in

exactly - one line.
- Postulate 1-4
- Through any three noncollinear points there is

exactly one plane.

- What is the intersection of plane HGFE and plane

BCGF?

H

G

E

F

D

C

A

B

Name two planes that intersect in BF

Look in book at example 4, page 13

Homework

- Pg 13 1-37, 60-65