1. 1 1-3 Points, Lines, and Planes Objectives: Properly name points, lines, and planes Define collinear points, coplanar points, and coplanar lines Define postulate or axiom State the characteristics of intersections involving lines and planes

2. 2 Points and Space A point: Represents a specific location Is drawn as a dot Is named with a Capital letter – point A, point C Has no shape nor size Space – The set of all points A C

3. 3 Line A line: Represents a series of points that extends in two opposite directions with no end Is drawn with an arrowhead at each end Is named by letters representing two points on the line (need two arrowheads above letters) or a lowercase script letter Collinear points: Points that lie on the same line t B A Line t or AB  BA  or

4. 4 Collinear points Are each of the following collinear? –Points E, D, and G –Points E, D, and F –Points H, D, E, and G G D E F H

5. 5 Plane Is a flat surface that extends without end Is often represented by a parallelogram, but a plane actually has no boundaries since it extends forever Is named by a Capital script letter or at least three noncollinear points on the plane B A C M Possible Names Include: Plane M or plane ABC or plane BAC or plane ADC or plane ADBC D

6. 6 Coplanar points and lines Points and lines that lie entirely on the same plane are coplanar Are each of following points are coplanar? –Points F, E, and G –Points D, G, E, and H –Points D, E, F G D E F H

7. 7 Postulate 1-1 Line Through Two Points Postulate/axiom – Statement accepted as fact Postulate 1-1: Through any two points, there is exactly one line. B A

8. 8 Postulate 1-2 Intersection of 2 lines If two distinct lines intersect, they intersect in exactly one point. A D C B E

9. 9 Postulate 1-3 Intersection of 2 planes If two distinct planes intersect, they intersect in exactly one line. M N D E

10. 10 Postulate 1-4 Noncollinear Points and Plane Through any three noncollinear points, there is exactly one plane. A B C

11. 11 Learning Check and Summary Which of the following represents a location in space? - Point, line, plane Which of the following extends in two opposite directions? – Point, line, plane Which of the following is basically a flat surface? – Point, line, plane If several points lie on the same line, they are ____?_____ If several points lie on the same plane, they are ___?___ If two planes intersect, they intersection is a ____?_____

12. 12 Exercises Workbook p. 10-12