1. Brett Solberg - Alta High ‘11
Geometry
Brett Solberg - Alta High ‘11

2. Warm-up What are the next 2 numbers in the series?
1, 4, 9, 16, 25, 36, , ,
5, 10, 9, 18, 17, 34, , ,
Get out your homework, your signed disclosure, and your notes.

3. Brief History of Geometry
Greek geo = earth metria = measure
Using math as an aid in real life.
Geometry: the study of the properties and relationships between points, lines, angles, curves and shapes.

4. Babylonian Geometry
7289 BC

5. Egyptian Geometry
2700 BC – 1500 BC

6. Chinese Geometry

7. Greek Geometry 600 BC Learned from the Egyptians
Educational rather than practical
Connected geometry to divinity
“Let no man ignorant of geometry enter here.” Sign above Plato’s Academy

8. Euclid 300 BC Greece Euclid’s Elements 10 postulate 465 propositions
Standard textbook for 2,000 years

9. Today’s Objectives
To understand basic terms and postulates of geometry.
To identify segments and rays and identify parallel lines.

10. Basic Elements of Geometry
Point
Space
Collinear Points
Line
Plane
Coplanar

11. Point
A point is a location.
A point has no size.

12. Collinear Points Points that lie on the same line.
Points A and B are collinear.

13. Line
A series of points that extend in opposite directions without end. l
Line l

14. Naming a line
There are many ways to identify this line. l

15. Plane
A flat surface containing many lines and points which extends in the direction of its lines without end. P
Plane P
Plane ABC
Plane BCA

16. Coplanar Points and lines which lie on the same plane.
Line l and points p and r are
all coplanar. r l p

17. Example 1

18. Example 2

19. Postulate
An accepted statement or fact.
Rules of the game.

20. Postulate 1.1
Postulate 1.2
Postulate 1.3
Postulate 1.4

21. Quick Break http://www.youtube.com/watch?v=dTAAsCNK7RA&ob=av2e
Fun with treadmills

22. Segment
Part of a line consisting of 2 endpoints and all the points between them.
What is the difference between
PQ PQ

23. Ray
Part of a line consisting of one endpoint and the points on one side of the endpoint. EF
Why is it called a sun ray?

24. Opposite Rays Two collinear rays with the same end point.
Opposite rays form a line.

25. Skew Lines
Non-coplanar lines, lines that do not intersect.

26. Parallel Lines Coplanar lines that do not intersect. AB || CD
What other examples of parallel lines in the real world can you think of?

27. Parallel Planes
Planes that do not intersect.

28. Example 1

29. Example 2

30. Homework Time 1.3 1.4 worksheets
Use the rest of class to complete the worksheets. I will come around to answer questions.