Download presentation

Presentation is loading. Please wait.

1
**What are the undefined terms?**

Aim: What are the undefined terms? Do Now: What is a point? What is a line? What is a plane? The most fundamental concepts in geometry do not have precise definitions but, we understand their meanings intuitively. We say these concepts are undefined. Geometry Leeson: Undefined Terms, Lines, Line Segments

2
**Geometry Leeson: Undefined Terms, Lines, Line Segments**

3
**. P . A(2, 6) A point indicates a position or location in space.**

X Y . A(2, 6) Points are named using capital letters and/or coordinates. Geometry Leeson: Undefined Terms, Lines, Line Segments

4
**A line is an infinite set of adjacent points.**

Ex: Curved line Ex: Straight line Naming a Line: Two points on the line: Single lowercase letter A B C m Geometry Leeson: Undefined Terms, Lines, Line Segments

6
**A plane is a set of points that forms a completely flat surface.**

Naming a Plane: Three points on the plane: Single uppercase letter: A • C• B • Plane ABC R Plane R Geometry Leeson: Undefined Terms, Lines, Line Segments

7
Intersections? Lines intersect at a point Planes intersect at a line

8
**Def: Collinear Points:**

A collinear set of points is a set of points all of which lie on the same straight line. A B C D E Points A, B, C and D are collinear. Points A, E and C are not collinear. Geometry Leeson: Undefined Terms, Lines, Line Segments

9
**Use the names of the endpoints.**

Def: Line Segment: A B A line segment is the set of two points on a line called endpoints, and all points on the line between the endpoints. Naming a Line Segment: Use the names of the endpoints. A B “Line segment” is part of “Line” Geometry Leeson: Undefined Terms, Lines, Line Segments

10
**Measure of Line Segments:**

The measure of a line segment is the length of the line segment. To indicate the “measure” of a line segment, use the name of the line segment without the line above the name. Ex: = “measure of line segment” Ex: The perimeter of is 58 cm. If AB = x - 4, BC = 2x + 8, and CA= x – 2, what is BC? Ans. BC=36 cm Geometry Leeson: Undefined Terms, Lines, Line Segments

11
**Def: Congruent Line Segments:**

Congruent line segments are segments that are equal in measure. Ex: A C D B If Then AB = CD Ans. CD = 29, AB = 29 Geometry Leeson: Undefined Terms, Lines, Line Segments

12
Def: Midpoint The midpoint of a line segment divides the line segment into two congruent segments. A B M 1) 3) 5) 2) 4) 6) Geometry Leeson: Undefined Terms, Lines, Line Segments

13
**X A B 1) 2) Def: Line Bisector**

The bisector of a line segment is a line that intersects the line segment at its midpoint. A B M P Q 1) 2) X Geometry Leeson: Undefined Terms, Lines, Line Segments

14
**Addition and Subtraction of Line Segments:**

If several line segments belong to the same line, we can write addition and subtraction expressions using the names of these segments. R P S Geometry Leeson: Undefined Terms, Lines, Line Segments

15
**Simple 2-Column Proof B P F E A Given Definition of Line Bisector**

Definition of Midpoint Geometry Leeson: Undefined Terms, Lines, Line Segments

Similar presentations

OK

Undefined Terms and Definitions 2-2A Why do we need undefined terms? What is a plane? What is a biconditional statement?

Undefined Terms and Definitions 2-2A Why do we need undefined terms? What is a plane? What is a biconditional statement?

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on frame relay and atm Ppt on contract labour act 1970 malaysia Ppt on you can win if you want modern Ppt on ozone layer Ppt on management by objectives drucker Ppt on natural resources and wildlife Ppt on second law of thermodynamics for kids Ppt on acid base and salts Ppt on chapter 12 electricity company Ppt on m commerce