M217 Section 1.1

Points, Lines, and Planes (oh my!)

2

DefinitionsTerm Definition Name/ExamplePoint

Line

Plane

3

DefinitionsTerm Definition ExampleCollinear

Coplanar

4

Term Definition Name/ExampleSegmentEndpointRay

Opposite Rays

a) Name 3 collinear pointsb) Name 3 non-collinear pointsc) List two opposite raysd) Are and the same?e) List 3 coplanar points

Example 1

AF

AG

Example 2a) Name a point coplanar with

– J, K, L– M, N, O– J, Q

b) Where do segments JQ and QN intersect?

c) Where do planes JQN and MNO intersect?

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Point Line and Plane Postulates• A postulate is a statement that is accepted without

proof.

• Through any 2 pts there is exactly 1 line

• Through any 3 noncollinear pts there is exactly one plane containing them

• When two lines intersect, the intersection is a point• When two planes intersect, the intersection is a line

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Drawing Planes• Plane G containing

two lines that intersect at point J

• Two planes that intersect at line SD