Applied Geometry Lesson 1 2 Points Lines and

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Applied Geometry Lesson 1 -2 Points, Lines, and Planes Objective: Learn to identify and

Applied Geometry Lesson 1 -2 Points, Lines, and Planes Objective: Learn to identify and draw models of points, lines, and planes, and determine their characteristics.

Point – the basic unit of geometry l Has no size l Named using

Point – the basic unit of geometry l Has no size l Named using CAPITAL Letters l Read as point A

Line – a series of points that extends without end in two directions. Made

Line – a series of points that extends without end in two directions. Made up of an infinite number of points Arrows show that the line extends without end in both directions Named: either a single lowercase script letter OR 2 points on the line Named: line l or

Example 1 Name two points on line m point P and point Q (or

Example 1 Name two points on line m point P and point Q (or Point R) Give 3 names for the line

Definitions Collinear – points that lie on the same line Noncollinear – points that

Definitions Collinear – points that lie on the same line Noncollinear – points that do not lie on the same line.

Example 3 Name three points that are collinear and three points that are noncollinear.

Example 3 Name three points that are collinear and three points that are noncollinear. Collinear – A, B, E or D, B, C Must have commas! Noncollinear – A, B, D or C, B, E or A, B, C or D, B, E Otherwise you are naming a plane.

Ray – has a definite starting point and extends without end in one direction.

Ray – has a definite starting point and extends without end in one direction. The starting point of a ray is called the endpoint. A ray is named using the endpoint first, then another point on the ray. *Naming a ray: arrow always points right!

Ray cont… Look at the pairs of rays

Ray cont… Look at the pairs of rays

Line Segment – a part of a line consisting of 2 endpoints and all

Line Segment – a part of a line consisting of 2 endpoints and all points between Name using its endpoints

Example Name 2 segments and one ray. Sample answers: Don’t name the same thing

Example Name 2 segments and one ray. Sample answers: Don’t name the same thing twice unless it asked for the different ways of naming. Why does ray BD not work?

Plane – a flat surface that extends without end in all directions For any

Plane – a flat surface that extends without end in all directions For any 3 noncollinear points, there is only one plane that contains all 3 points. A plane can be named with a single uppercase script letter or by three noncollinear points. Plane named: ABC or M

Definitions Coplanar – Points that lie in the same plane Noncoplanar – Points that

Definitions Coplanar – Points that lie in the same plane Noncoplanar – Points that do not lie in the same plane.

Hands-On Activity Place points B, C, D, E near the corners of a piece

Hands-On Activity Place points B, C, D, E near the corners of a piece of paper. Place point A in the middle of the paper Fold the paper so that point A is on the crease. Open the paper slightly. The two sections of the paper represent different planes. A, E, D l Name 3 points that are coplanar l Name 3 points that are noncoplanar D, A, C l Name a point that is in both planes A