1. Plane Geometry Unit 1 – Chapter 1
Section 1.1 – Identify Points, Lines, and Planes
Day 1

2. l Section 1.1 Notes P A B C LINE NOTATION:
Undefined Terms – Vocabulary without a formal definition, but overall agreement with what the term means. Point – representation of a unique location in space. It has no dimension. Line – connection of an infinite number of points. It has one dimension. P l A B C
LINE NOTATION:
Line l, Line AB ( AB ), Line ( BC ),
or Line AC ( AC )

3. Section 1.1 Notes AB A B A B AB A B AB RAY NOTATION:
Compare and Contrast: Line – Infinite in length, extends endlessly in opposite directions. Segment – Finite portion of a line that begins and ends at endpoints (points on that line). Ray – Infinitely long portion of a line that begins at an initial point and extends endlessly in one direction. AB A B A B AB
Endpoint A B AB
RAY NOTATION:
Point with no arrow head is called endpoint, always list endpoint first and always draw arrow pointing right.

4. Section 1.1 Notes
Extension: Opposite Rays – two rays that share the same endpoint but extend in exactly opposite directions. They =alwys form a straight line. What are the opposite rays for the image given?
Endpoint A H I HA HI

5. M Section 1.1 Notes PLANE NOTATION: W
Plane – a flat surface that contains an infinite amount of lines and extends endlessly in two directions. M
PLANE NOTATION:
Plane M, or Plane COW, Plane WOC, Plane OCW W O C
PLANE NOTATION:
Use any three points that lie on the plane and that do not lie in a line, or if a letter already represents it.

6. Section 1.1 Notes A B C D H G O S
Collinear Points – points that all lie on the same line. Coplanar Points – points that all lie on the same plane. A B C D H G O S

7. Section 1.1 Notes A
Identification, name: The plane: HOD, DOG, DGH A Line: AB, OB, HG, GO, … A Segment: GO, AO, BO, HG, … A Ray: OG, GH, BA, AB, HG, … D H O G B

8. Section 1.1 Notes E A D C B F Identification, Collinear or not? B, D
C, E
A, D
B, F
F, E, D
A, E, D
D, B, C
C, E, F
YES NO A D C B F

9. Section 1.1 Notes E A D C B F Identification, Coplanar or not? B, C, D
A, B, C
F, E, D
E, A, F
A, B, C, D
F, E, D, C
E, A, D, C
B, C, D, E, F
YES NO A D C B F

10. Section 1.1 Notes E C O P C M W F Intersections:
2 lines always intersect at a point (Figure 1)
A line that does not lie on a plane can intersect a plane at a point. (Figure 2) E C
Intersection O
Intersection P C M W
Figure 1
Figure 2 F

11. a M Q Section 1.1 Notes Intersections: (cont.)
2 Planes always intersect at a line (Figure 3) a M Q
Intersection: Line a
Figure 3

12. CHECK FOR UNDERSTANDING…Time to Draw…
Four coplanar points…three or which are collinear. A D C B

13. CHECK FOR UNDERSTANDING…Time to Draw…
Two coplanar lines that do NOT intersect. F E H B C D

14. CHECK FOR UNDERSTANDING…Time to Draw…
Opposite rays AB and AC.
Endpoint B A C AB AC

15. CHECK FOR UNDERSTANDING…Time to Draw…
Three planes that do not intersect. B A M

16. CHECK FOR UNDERSTANDING…Time to Draw…
Three coplanar lines that intersect at the same point. B F H E E C D B

17. CHECK FOR UNDERSTANDING…Time to Draw…
Two planes that intersect one another. a M Q

18. CHECK FOR UNDERSTANDING…Time to Draw…
Two lines that intersect and a third line that does not intersect either of them. E A G D C H B F

19. CHECK FOR UNDERSTANDING…Time to Draw…
Three lines that intersect at a point but are not coplanar. A D H O G F B

20. P. 3-5 #1 – 7 “Guided Practice”
CONCEPT CHECK
P. 3-5 #1 – 7 “Guided Practice”

21. HOMEWORK
P. 5-6 # (Omit #12)