Welcome Geometry MMrs. Rodriguez

Today is….

Tuesday, August 25, 2014First holiday – Monday

September 6th Labor day – No School

Agenda & News

Intro into Geometry Points, planes, Lines Group practice Assignment Ticket out

First holiday – Monday September 7th Labor day – No School

3 Act Math

https://media.pearsoncmg.com/curriculum/math/ma_hs16tx_gmte/scos/A0385746/player.html

Solve it!

https://media.pearsoncmg.com/curriculum/math/ma_hs16tx_gmte/scos/A0262632/player.html

Intro to Geometry

Geometry is a mathematical system built on accepted facts, basic terms, and definitions.

Points

Points – a location, that has no size. It is usually represented by a small dot and is named by a capital letter.

A geometric figure is a set of points.

Space – is defined as the set of all points.

A B C

Lines

Line – a series of points that extends in two opposite directions without end. You name a line by any two points on the

line, such as: AB

You can also name a line with a single lowercase letter, such as line t.

Collinear Points – Points that lie on the same line

A B t

Practice

Name all points, and lines, if there are any.

1.

2.

3.

4.

Planes

Plane – is a flat surface that has no thickness A plane contains many lines and extends

without end in the directions of all its lines.

You can name a plane by either a single capital letter or at least three of its non collinear points.

Coplanar – Points and lines in the same plane

P

A

B

C

Plane P Plane ABC

Segment

Segments: are part of a line consisting of 2 endpoints and all points between them.

Rays

Rays- are the part of a line consisting of one endpoint and all the points of the line on one side of the end point.

Opposite Rays

Opposite Rays – are 2 collinear rays with the same end point. Opposite rays always form a line.

Postulate 1-1

Postulate 1-2

Postulate 1-3

Postulate 1-4

Got it!

QS RQ SR

Line l

Plane RVSPlane VQS

Why not Plane RQS?

N, Q, T

Got it!

N, T

It is 3 o’clock!

Discuss the following questions with a partner and justify your answer. Given two points, are they sometimes, always, or never collinear? Given two lines, are they sometimes, always, or never coplanar? As you listen to your partner, confirm that your understanding of the vocabulary is consistent with theirs.

Got it #2

DE EF DF

ED FE FD

No, they do not have the same endpoint.Name all the rays in the picture.

Ticket out

How far does a line go in each direction?

What is it called when points are on the same line?

How many directions does a line have?