Points, Lines, Planes

Points, Lines, PlanesChapter 1 Section 2ObjectiveStudents will understand basic terms and postulates of Geometry.

PointA specific location in space

It has no size, width, or depth

It is named by a Capital Letter

LineAn infinite collection of points in a straight path that extends forever in two directions.

Has no size, width, or depth

It is named by any two points on the line or by a lower case cursive letter.PlaneA flat surface that extends forever without end in four directions.

It is named by a any three points on the plane or by a capitol cursive letter.

It has no size, width, or depth

Collinear PointsPoints on the same line

Can be used to name the lineCoplanarOn the same plane

Remember: a plane contains an infinite number of points and lines.Turn to Page 12.Look at Problem 1

Try the Got It problem for this example.SpaceThe set of all points in three dimensions.

It contains the universe =)

SegmentPart of a lineIt has a definite beginning and an endIt is named by its two endpoints.ABRay Half of a lineIt extends forever in one direction and has one endpoint.

It is named by its endpoint and any other point on the ray.

ABOpposite RayTwo rays that share the same endpoint and extend in opposite directions

It makes a lineTurn to Page 13Look at Problem 2

Try the Got It ProblemsPostulateAn accepted statement of fact

Also known as an axiom

Basic building block of Geometry

Postulate 1-1Through any two points there is exactly one lineIntersectionThe set of points two figures have in common

Where the two figures overlapPostulate 1-2Two lines intersect at a pointPostulate 1-3Two planes intersect at a line

Turn to Page 14Look at Example 3

Try the Got It problem for that example.Postulate 1-4Through any three noncollinear points there is exactly one plane

On page 15..Look at Example 4

Try the Got It problem for that exampleOn Page 16Try Problems #1-7 on your own.

Raise your hand when you have completed them.