Foundations for Geometry, Study notes of Geometry

1-5 Using Formulas in Geometry. Connecting Geometry to Algebra Graphing in the Coordinate ... Key Chapter 1 resources and assessments modified to address.

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2A Chapter 1
RESOURCE OPTIONS • RESOURCE OPTIONS • RESOURCE OPTIONS • RESOURCE
E
O
Foundations for Geometry
Section 1A Section 1B
Euclidean and Construction Tools Coordinate and Transformation Tools
1-1 Understanding Points, Lines, and Planes
1-2 Technology Lab Explore Properties Associated with Points
1-2 Measuring and Constructing Segments
1-3 Measuring and Constructing Angles
1-4 Pairs of Angles
1-5 Using Formulas in Geometry
Connecting Geometry to Algebra Graphing in the Coordinate
Plane
1-6 Midpoint and Distance in the Coordinate Plane
1-7 Transformations in the Coordinate Plane
1-7 Technology Lab Explore Transformations
Pacing Guide for 45-Minute Classes
Chapter 1 Countdown to Testing Weeks 1, 2
DAY 1 DAY 2 DAY 3 DAY 4 D AY 5
1-1 Lesson 1-2 Technology Lab
1-2 Lesson
1-3 Lesson 1-4 Lesson
Multi-Step Test Prep
Ready to Go On?
DAY 6 D AY 7 DAY 8 DAY 9 DAY 10
1-5 Lesson
Connecting Geometry
to Algebra
1-6 Lesson
1-7 Lesson 1-7 Technology Lab
Multi-Step Test Prep
Ready to Go On?
DAY 11 DAY 12
Chapter 1 Review Chapter 1 Test
Pacing Guide for 90-Minute Classes
Chapter 1
DAY 1DAY 2DAY 3DAY 4DAY 5
1-1 Lesson
1-2 Technology Lab
1-2 Lesson
1-3 Lesson
1-4 Lesson
Multi-Step Test Prep
Ready to Go On?
1-5 Lesson
Connecting Geometry
to Algebra
1-6 Lesson
1-7 Lesson
1-7 Technology Lab
Multi-Step Test Prep
Ready to Go On?
DAY 6
Chapter 1 Review
Chapter 1 Test
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2A Chapter 1

RESOU RCE OPTIONS • RESOURCE OPTIONS • RESOU RCE OPTIONS • RESOU RCEE

Foundations for Geometry

Section 1A Section 1B

Euclidean and Construction Tools Coordinate and Transformation Tools

1-1 Understanding Points, Lines, and Planes

1-2 Technology Lab Explore Properties Associated with Points

1-2 Measuring and Constructing Segments

1-3 Measuring and Constructing Angles

1-4 Pairs of Angles

1-5 Using Formulas in Geometry

Connecting Geometry to Algebra Graphing in the Coordinate

Plane

1-6 Midpoint and Distance in the Coordinate Plane

1-7 Transformations in the Coordinate Plane

1-7 Technology Lab Explore Transformations

Pacing Guide for 45-Minute Classes

Chapter 1 Countdown to Testing Weeks^1 ,^2

DAY 1 DAY 2 DAY 3 DAY 4 DAY 5

1-1 Lesson 1-2 Technology Lab

1-2 Lesson

1-3 Lesson 1-4 Lesson Multi-Step Test Prep

Ready to Go On?

DAY 6 DAY 7 DAY 8 DAY 9 DAY 10

1-5 Lesson Connecting Geometry

to Algebra

1-6 Lesson

1-7 Lesson 1-7 Technology Lab Multi-Step Test Prep

Ready to Go On?

DAY 11 DAY 12

Chapter 1 Review Chapter 1 Test

Pacing Guide for 90-Minute Classes

Chapter 1

DAY 1 DAY 2 DAY 3 DAY 4 DAY 5

1-1 Lesson

1-2 Technology Lab

1-2 Lesson

1-3 Lesson

1-4 Lesson

Multi-Step Test Prep

Ready to Go On?

1-5 Lesson

Connecting Geometry

to Algebra

1-6 Lesson

1-7 Lesson

1-7 Technology Lab

Multi-Step Test Prep

Ready to Go On?

DAY 6

Chapter 1 Review

Chapter 1 Test

2B

OPTIONS • RESOU RCE OPTIONS • RESOURCE OPTIONS • RESOURCE OPTIONS

Before Chapter 1 Testing

Diagnose mastery of concepts in the chapter.

Ready to Go On? SE pp. 35, 59

Multi-Step Test Prep SE pp. 34, 58

Section Quizzes AR pp. 5–

Test and Practice Generator

Prescribe intervention.

Ready to Go On? Intervention pp. 2–

Scaffolding Questions TE pp. 34, 58

Before High Stakes Testing

Diagnose mastery of benchmark concepts.

College Entrance Exam Practice SE p. 65

New York Test Prep SE pp. 68–

Prescribe intervention.

College Entrance Exam Practice

New York State Test Prep Workbook

Before Every Lesson

Diagnose readiness for the lesson.

Warm Up TE, every lesson

Prescribe intervention.

Skills Bank SE pp. S50–S

Reteach CRB, Ch. 1

During Every Lesson

Diagnose understanding of lesson concepts.

Check It Out! SE, every example

Think and Discuss SE, every lesson

Write About It SE, every lesson

Journal TE, every lesson

Prescribe intervention.

Questioning Strategies TE, every example

Reading Strategies CRB, every lesson

Success for ELL pp. 1–

After Every Lesson

Diagnose mastery of lesson concepts.

Lesson Quiz TE, every lesson

Alternative Assessment TE, every lesson

Test Prep SE, every lesson

Test and Practice Generator

Prescribe intervention.

Reteach CRB, every lesson

Problem Solving CRB, every lesson

Test Prep Doctor TE, every lesson

Homework Help Online

DIAGNOSE PRESCRIBE

KEY: SE = Student Edition TE = Teacher’s Edition CRB = Chapter Resource Book AR = Assessment Resources Available online Available on CD-ROM

Assess

Prior

Knowledge

After Chapter 1

Check mastery of chapter concepts.

Multiple-Choice Tests (Forms A, B, C)

Free-Response Tests (Forms A, B, C)

Performance Assessment AR pp. 7–

Test and Practice Generator

Check mastery of benchmark concepts.

New York State Regents Exam

College Entrance Exams

Prescribe intervention.

Reteach CRB, every lesson

Lesson Tutorial Videos Chapter 1

Prescribe intervention.

New York State Test Prep Workbook

College Entrance Exam Practice

Summative

Assessment

Before Chapter 1

Diagnose readiness for the chapter.

Are You Ready? SE p. 3

Prescribe intervention.

Are You Ready? Intervention Skills 20, 57, 60, 79

Formative

Assessment

2D

OPTIONS • RESOU RCE OPTIONS • RESOURCE OPTIONS • RESOURCE OPTIONS

Lesson Tutorial Videos Multilingual Glossary Online Interactivities

Starring Holt authors Ed Burger and Freddie

Renfro! Live tutorials to support every

lesson in Chapter 1.

Searchable glossary includes definitions

in English, Spanish, Vietnamese, Chinese,

Hmong, Korean, and 4 other languages.

Interactive tutorials provide visually engaging

alternative opportunities to learn concepts and

master skills.

Technology Highlights for Reaching All Learners

KEY: SE = Student Edition TE = Teacher’s Edition CRB = Chapter Resource Book JG8E@J? Spanish version available Available online Available on CD-ROM

Reaching All Learners

Resources for All Learners

Geometry Lab Activities ....................................... Chapter 1

Technology Lab Activities ..................................... Chapter 1

New York Homework and Practice Workbook .........pp. 1–

Know-It Notebook .............................................. Chapter 1

New York Problem Solving Workbook ....................pp. 1–

DEVELOPING LEARNERS

Practice A .............................................. CRB, every lesson

Reteach ................................................. CRB, every lesson

Inclusion ..........................TE pp. 18, 25, 30, 36, 42, 45, 51

Questioning Strategies ............................ TE, every example

Modifi ed Chapter 1 Resources ................. IDEA Works!

Homework Help Online

ON-LEVEL LEARNERS

Practice B ............................................... CRB, every lesson

Multiple Representations ........................................TE p. 18

Cognitive Strategies ........................................TE pp. 29, 44

ADVANCED LEARNERS

Practice C ............................................... CRB, every lesson

Challenge ............................................... CRB, every lesson

Reading and Writing Math EXTENSION ...........................TE p. 5

Multi-Step Test Prep EXTENSION ..........................TE pp. 34, 58

Critical Thinking .....................................................TE p. 14

English Language Learners

Are You Ready? Vocabulary...................................... SE p. 3

Vocabulary Connections ........................................... SE p. 4

Lesson Vocabulary .....................................SE, every lesson

Vocabulary Exercises .........................SE, every exercise set

Vocabulary Review ................................................ SE p. 60

English Language Learners ..........TE pp. 5, 7, 14, 22, 23, 39

Reading Strategies .................................. CRB, every lesson

Success for English Language Learners ...................pp. 1–

Multilingual Glossary

Reaching All Learners Through...

Inclusion ..........................TE pp. 18, 25, 30, 36, 42, 45, 51

Visual Cues ........................................TE pp. 21, 22, 27, 30

Kinesthetic Experience ....................................TE pp. 18, 26

Concrete Manipulatives...................................TE pp. 14, 51

Multiple Representations ........................................TE p. 18

Cognitive Strategies ........................................TE pp. 29, 44

Cooperative Learning ..............................................TE p. 29

Modeling .................................................................TE p. 7

Critical Thinking .....................................................TE p. 14

Test Prep Doctor .................................TE pp. 11, 26, 33, 40

49, 55, 65, 66, 68

Common Error Alerts .........................TE pp. 15, 19, 21, 23,

25, 29, 39, 45, 49

Scaffolding Questions .....................................TE pp. 34, 58

E NGLISH

L ANGUAGE

L EARNERS

2E Chapter 1

RESOU RCE OPTIONS • RESOURCE OPTIONS • RESOU RCE OPTIONS • RESOU RCEE

Ongoing Assessment

KEY: SE = Student Edition TE = Teacher’s Edition AR = Assessment Resources JG8E@J? Spanish version available Available online Available on CD-ROM

Are You Ready? JG8E@J? Ready to Go On? Test and Practice Generator

Automatically assess readiness and

prescribe intervention for Chapter 1

prerequisite skills.

Automatically assess understanding

of and prescribe intervention for

Sections 1A and 1B.

Use Chapter 1 problem banks to create

assessments and worksheets to print out or

deliver online. Includes dynamic problems.

Technology Highlights for Ongoing Assessment

Assessing Prior Knowledge

Determine whether students have the prerequisite concepts

and skills for success in Chapter 1.

Are You Ready? JG8E@J? ........................... SE p. 3

Warm Up ................................... TE, every lesson

Test Preparation

Provide review and practice for Chapter 1 and standardized

tests.

Multi-Step Test Prep ...................................... SE pp. 34, 58

Study Guide: Review ...................................... SE pp. 60–

Test Tackler ................................................... SE pp. 66–

New York Test Prep ....................................... SE pp. 68–

College Entrance Exam Practice .............................. SE p. 65

New York State Test Prep Workbook

IDEA Works!

Alternative Assessment

Assess students’ understanding of Chapter 1 concepts

and combined problem-solving skills.

Chapter 1 Project ..................................................... SE p. 2

Alternative Assessment .............................. TE, every lesson

Performance Assessment ............................... AR pp. 19–

Portfolio Assessment ......................................... AR p. xxxiv

Daily Assessment

Provide formative assessment for each day of Chapter 1.

Questioning Strategies ............................ TE, every example

Think and Discuss ......................................SE, every lesson

Check It Out! Exercises ............................SE, every example

Write About It ...........................................SE, every lesson

Journal...................................................... TE, every lesson

Lesson Quiz ............................... TE, every lesson

Alternative Assessment .............................. TE, every lesson

Modifi ed Lesson Quizzes ......................... IDEA Works!

Weekly Assessment

Provide formative assessment for each week of Chapter 1.

Multi-Step Test Prep ...................................... SE pp. 34, 58

Ready to Go On? ............................ SE pp. 35, 59

Cumulative Assessment ................................. SE pp. 68–

Test and Practice Generator ............. One-Stop Planner

Formal Assessment

Provide summative assessment of Chapter 1 mastery.

Section Quizzes ................................................. AR pp. 5–

Chapter 1 Test ....................................................... SE p. 64

Chapter Test (Levels A, B, C) ............................. AR pp. 7–

  • Multiple Choice • Free Response

Cumulative Test ............................................. AR pp. 21–

Test and Practice Generator ............. One-Stop Planner

Modifi ed Chapter 1 Test .......................... IDEA Works!

2 Chapter 1

1A Euclidean and

Construction Tools

1-1 Understanding Points, Lines,

and Planes

Lab Explore Properties Associated

with Points

1-2 Measuring and Constructing

Segments

1-3 Measuring and Constructing

Angles

1-4 Pairs of Angles

1B Coordinate and

Transformation Tools

1-5 Using Formulas in Geometry

1-6 Midpoint and Distance in the

Coordinate Plane

1-7 Transformations in the

Coordinate Plane

Lab Explore Transformations

Picture This!

Many geometric concepts and shapes

may be used in creating works of art.

Unique designs can be made using

only points, lines, planes, or circles.

KEYWORD: MG7 ChProj

Foundations

for Geometry

ge07se_c01_0002_0005.indd 1 11/23/06 1:22:27 PM

2 Chapter 1

S E C T I O N 1A

Euclidean and

Construction Tools

On page 34, stu-

dents analyze a

diagram of an

archaeological dig by

applying definitions, using the dis-

tance formula, and classifying angles.

Exercises designed to prepare stu-

dents for success on the

Multi-Step Test Prep can

be found on pages 10,

18, 26, and 32.

S E C T I O N 1B

Coordinate and

Transformation Tools

On page 58, stu-

dents find the area

and perimeter of a

patio to determine

the total cost of the paving stones

used. They use distance, midpoint,

and transformations to create the

construction plans for the patio.

Exercises designed to prepare stu-

dents for success on the

Multi-Step Test Prep can

be found on pages 39,

48, and 54.

About the Project

Students begin by using geoboards to

explore designs based on line segments.

Then they use a compass and paper folding

to make star designs. Finally, students use

everything they’ve learned to produce an

original piece of string art.

Picture This

Project Resources

All project resources for teachers and stu-

dents are provided online.

Materials:

- Activity 1: geoboard, colored rubber

bands or colored string

- Activity 2: compass, straightedge - Activity 3: straightedge - Activity 4: wooden board, small nails,

hammer, colored string or thread

KEYWORD: MG7 ProjectTS

Foundations for Geometry 3

Vocabulary

Match each term on the left with a definition on the right.

1. coordinate

2. metric system

of measurement

3. expression

4. order of operations

Measure with Customary and Metric Units

For each object tell which is the better measurement.

5. length of an unsharpened pencil 6. the diameter of a quarter

__^1

in. or 9

3 __

in. 1 m or 2

__^1

cm

7. length of a soccer field 8. height of a classroom

100 yd or 40 yd 5 ft or 10 ft

9. height of a student’s desk 10. length of a dollar bill

30 in. or 4 ft 15.6 cm or 35.5 cm

Combine Like Terms

Simplify each expression.

11. - y + 3 y - 6 y + 12 y 12. 63 + 2 x - 7 - 4 x

13. - 5 - 9 - 7 x + 6 x 14. 24 - 3 y + y + 7

Evaluate Expressions

Evaluate each expression for the given value of the variable.

15. x + 3 x + 7 x for x = - 5 16. 5 p + 10 for p = 78

17. 2 a - 8 a for a = 12 18. 3 n - 3 for n = 16

Ordered Pairs

Write the ordered pair for each point.

{ n

 n

n

Þ

Ý

 { ä

19. A 20. B

21. C 22. D

23. E 24. F

A. a mathematical phrase that contains operations, numbers,

and/or variables

B. the measurement system often used in the United States

C. one of the numbers of an ordered pair that locates a point

on a coordinate graph

D. a list of rules for evaluating expressions

E. a decimal system of weights and measures that is used

universally in science and commonly throughout the world

C

E

A

D

_ 1

in. 2

_ 1

cm

100 yd 10 ft

30 in. 15.6 cm

8 y - 2 x + 56

- x - 14 - 2 y + 31 **- 55 400

  • 72 45**

(0, 7) (-5, 4)

(6, 3) (-8, - 2 )

(3, - 5 ) (6, - 4 )

ge07se_c01_0002_0005.indd 3 4/27/06 11:56:23 AM

Are You Ready? 3

NO

INTERVENE (^) Diagnose and Prescribe

ARE Y OU R EADY? Intervention, Chapter 1

Prerequisite Skill Worksheets CD-ROM Online

Measure with Customary and Metric Units Skill 20 Activity 20

Diagnose and

Prescribe Online

Combine Like Terms Skill 57 Activity 57

Evaluate Expressions Skill 60 Activity 60

Ordered Pairs Skill 79 Activity 79

YES

ENRICH

ARE YOU READY?

Enrichment, Chapter 1

Worksheets

CD-ROM

Online

Organizer

Objective: Assess students’

understanding of prerequisite skills.

Prerequisite Skills

Measure with Customary and

Metric Units

Combine Like Terms

Evaluate Expressions

Ordered Pairs

Assessing Prior

Knowledge

INTERVENTION

Diagnose and Prescribe

Use this page to determine

whether intervention is necessary

or whether enrichment is

appropriate.

Resources

Are You Ready?

Intervention and

Enrichment Worksheets

Are You Ready? CD-ROM

Are You Ready? Online

Foundations for Geometry 5

Reading Strategy: Use Your Book for Success

Understanding how your textbook is organized will help you locate and use

helpful information.

Try This

Use your textbook for the following problems.

1. Use the index to find the page where right angle is defined.

2. What formula does the Know-It Note on the first page of

Lesson 1-6 refer to?

3. Use the glossary to find the definition of congruent segments.

4. In what part of the textbook can you find help for solving equations?

As you read through an example problem, pay attention to the notes in

the margin. These notes highlight key information about the concept

and will help you to avoid common mistakes.

The Glossary is found

in the back of your

textbook. Use it when

you need a definition

of an unfamiliar word

or phrase.

The Index is located at the

end of your textbook. If

you need to locate the page

where a particular concept

is explained, use the Index

to find the corresponding

page number.

The Skills Bank is located in

the back of your textbook.

Look in the Skills Bank for

help with math topics that

were taught in previous

courses, such as the order

of operations.

ge07se_c01_0002_0005.indd 5 12/13/06 12:09:55 PM

New York Performance Indicators

Performance

Indicators 1-

LAB

LAB

G.G.17 (^) ★

G.G.48 ★

G.G.54 ★

G.G.55 ★

G.G.56 ★

G.G.66 ★

G.G.67 ★

G.PS.5 ★ ★

G.CM.11 ★ ★

G.CN.6 ★ ★

New York Mathematics Performance Indicators are written out completely on pp NY28-NY35.

Reading and Writing Math 5

Organizer

Objective: Help students apply

strategies to understand and retain

key concepts.

G

I

D

@<I

Online Edition

Resources

Chapter 1 Resource Book

Reading Strategies

Reading Strategy:

E NGLISH

L ANGUAGE

L EARNERS

Use Your Book for

Success

Discuss The index, glossary, margin

notes, and Skills Bank can provide

students with a great deal of use-

ful information as they use this

textbook. Have students divide

their journal into sections such as

research, reflections, constructions,

postulates, and so on. Encourage

them to use all the resources pro-

vided in this book.

Extend Ask students to find a term

they do not know and look it up

in the glossary. Then ask them to

enter the definition in their jour-

nal. Challenge the students to use

information in the book that was

not mentioned. For example, look

at the table of contents, highlighted

words, words in italics, or words in

boldface.

Answers to Try This

1. p. 21

2. Mdpt. Formula

3. segs. that have the same length

4. Skills Bank

C H A P T E R

1

6A Chapter 1

Euclidean and Construction Tools

One-Minute Section Planner

Lesson Lab Resources Materials

Lesson 1-1 Understanding Points, Lines, and Planes

-

Identify, name, and draw points, lines, segments, rays, and planes.

-

Apply basic facts about points, lines, and planes.

NY Regents Exam

□✔^

SAT-

□✔^

NAEP

□✔^

ACT

□✔^

SAT

Required

straightedge (MK)

Optional

raw spaghetti, index cards,

straw, clay, gumdrops,

toothpicks

1-2 Technology Lab Explore Properties Associated with Points

-

Use geometry software to measure distances and explore properties

of points on segments.

NY Regents Exam

□✔^

SAT-

□✔^

NAEP

□✔^

ACT

SAT

Technology Lab Activities

1-2 Lab Recording Sheet

Required

geometry software

Optional

ruler (MK)

Lesson 1-2 Measuring and Constructing Segments

-

Use length and midpoint of a segment.

-

Construct midpoints and congruent segments.

NY Regents Exam

□✔^

SAT-

□✔^

NAEP

□✔^

ACT

□✔^

SAT

Geometry Lab Activities

1-2 Geometry Lab

Required

compass (MK), straightedge

Optional

road map, masking tape,

butcher paper, small plastic

disks, meter stick

Lesson 1-3 Measuring and Constructing Angles

-

Name and classify angles.

-

Measure and construct angles and angle bisectors.

□✔^ NY Regents Exam^ □ SAT-10^ □✔^ NAEP^ □✔^ ACT^ □✔^ SAT

Geometry Lab Activities

1-3 Geometry Lab

Required

compass (MK), straightedge,

protractor (MK), geometry

software

Optional

yarn, index cards, pictures of

angles, origami paper, sticky

notes, acetate or tracing paper,

clock (MK), Mira

Lesson 1-4 Pairs of Angles

-

Identify adjacent, vertical, complementary, and supplementary

angles.

-

Find measures of pairs of angles.

□ NY Regents Exam^ □ SAT-10^ □✔^ NAEP^ □✔^ ACT^ □✔^ SAT

Required

protractor (MK)

MK = Manipulatives Kit

6 Chapter 1 Foundations for Geometry

The most basic figures in geometry are undefined

terms , which cannot be defined by using other

figures. The undefined terms point, line, and plane

are the building blocks of geometry.

TERM NAME DIAGRAM

A point names a location

and has no size. It is

represented by a dot.

A capital letter

point P

A line is a straight path

that has no thickness and

extends forever.

A lowercase letter or

two points on the line

line  ,  XY  or YX 

A plane is a flat surface

that has no thickness and

extends forever.

A script capital letter

or three points not

on a line

plane R or plane ABC

Undefined Terms

Points that lie on the same line are collinear. K , L ,

and M are collinear. K, L, and N are noncollinear.

Points that lie in the same plane are coplanar.

Otherwise they are noncoplanar.

E X A M P L E 1 Naming Points, Lines, and Planes

A Name four coplanar points.

K, L, M, and N all lie in plane R.

B Name three lines.

 AB  , BC  , and  CA .

1. Use the diagram to

name two planes.

1-

Understanding Points,

Lines, and Planes

A plane may be

named by any three

noncollinear points

on that plane. Plane

ABC may also be

named BCA , CAB ,

CBA , ACB , or BAC.

Objectives

Identify, name, and draw

points, lines, segments,

rays, and planes.

Apply basic facts about

points, lines, and planes.

Vocabulary

undefined term

point

line

plane

collinear

coplanar

segment

endpoint

ray

opposite rays

postulate

Who uses this?

Architects use representations of points, lines, and

planes to create models of buildings. Interwoven

segments were used to model the beams of

Beijing’s National Stadium for the 2008 Olympics.

Refer to the design in the roof of

Beijing’s National Stadium.

NY Performance

Indicators

G.CM.11 Understand and

use appropriate language,

representations, and terminology

when describing objects,

relationships, mathematical

solutions, and geometric

diagrams. Also, G.CN.6.

Possible answer:

plane R and plane ABC

ge07se_c01_0006_0011.indd 1 11/23/06 1:23:25 PM

6 Chapter 1

New York Performance

Indicators

Process

G.CM.11 Understand and use

appropriate language, representations,

and terminology when describing

objects, relationships, mathematical

solutions, and geometric diagrams

G.CN.6 Recognize and apply

mathematics to situations in the

outside world

Motivate

Point out different objects in the classroom that

are representations of points, segments, and

planes, such as the tips of pushpins on the bul-

letin board, rulers, and desktops. Discuss with stu-

dents what these items have in common.

Ask students to give examples of other objects

that have these same characteristics and can be

found in the world around them, such as the loca-

tions of cities on a map, the lines on a football

field, and the bases on a baseball field.

Introduce

1

Explorations and answers are provided in the

Explorations binder.

1-1 Organizer

Pacing: Traditional 1 day

Block

__^1

day

Objectives: Identify, name, and

draw points, lines, segments, rays,

and planes.

Apply basic facts about points,

lines, and planes.

G

I

D

@<I

Online Edition

Tutorial Videos, Interactivity

Countdown to

Testing Week 1

Warm Up

Graph each inequality.

1. x ≥ 3

 Ó ä Ó {

2. 2 ≤ x ≤ 6

ä Ó { È

3. x < 1 or x > 0

ä £

Also available on transparency

Q: What did the little acorn say

when it grew up?

A: “Geometry”

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1- 1 Understanding Points, Lines, and Planes 7

DEFINITION NAME DIAGRAM

A segment , or line segment,

is the part of a line consisting

of two points and all points

between them.

The two endpoints

AB or

BA 

An endpoint is a point at

one end of a segment or the

starting point of a ray.

A capital letter

C and D

A ray is a part of a line

that starts at an endpoint

and extends forever in one

direction.

Its endpoint and any other

point on the ray

 RS

- ,

Opposite rays are two

rays that have a common

endpoint and form a line.

The common endpoint and

any other point on each ray

 EF  and  EG 

Segments and Rays

E X A M P L E 2 Drawing Segments and Rays

Draw and label each of the following.

A a segment with endpoints U and V

B opposite rays with a common endpoint Q

2. Draw and label a ray with endpoint M that contains N.

A postulate , or axiom, is a statement that is accepted as true without proof.

Postulates about points, lines, and planes help describe geometric properties.

1-1-1 Through any two points there is exactly

one line.

1-1-2 Through any three noncollinear points there

is exactly one plane containing them.

1-1-3 If two points lie in a plane, then the line

containing those points lies in the plane.

Postulates Points, Lines, and Planes

E X A M P L E 3 Identifying Points and Lines in a Plane

Name a line that passes through two points.

There is exactly one line n passing through

G and H.

3. Name a plane that contains three noncollinear points.

Possible answer: plane GHF

M N

ge07se_c01_0006_0011.indd 7 12/2/05 7:08:00 PM

Lesson 1-1 7

Guided Instruction

Show students how to draw a plane.

Discuss all the different ways of labeling a

line, segment, ray, and plane. Explain that

CD  and DC  are not the same ray.

Visual Point out to students that

the diagrams of planes, lines, and

rays extend forever, but we can-

not draw them that way.

Teach

2

Through Modeling

Have students work in small groups to use

physical models, such as raw spaghetti and

index cards, to illustrate Postulates 1-1-3,

1-1-4, and 1-1-5. Use contrasting colors of

paper to emphasize the different planes in

Postulate 1-1-5.

Example 1

A. Name four coplanar points.

A, B, C, D

B. Name three lines.

Possible answer:  AE ,   BE ,   CE 

Example 2

Draw and label each of the

following.

A. segment with endpoints M

and N 

B. opposite rays with common

endpoint T

Example 3

Name a line that passes through

two points.  XY 

Also available on transparency

Additional Examples

Reading Math

The phrase

“exactly one”

means that one exists

and it is unique.

E NGLISH

L ANGUAGE

L EARNERS

INTERVENTION

Questioning Strategies

EX AM P LE 1

  • What are the different ways you

can name the planes represented

in the stadium roof?

  • How else could you name the

lines?

EX AM P LE 2

  • What figure is formed by two

opposite rays? Is there a way to

name the opposite rays? Give an

example.

EX AM P LE 3

  • Are there other ways to name the

line determined by the points in

the diagram? Explain.

1- 1 Understanding Points, Lines, and Planes 9

Exercises Exercises

1-

GUIDED PRACTICE

Vocabulary Apply the vocabulary from this lesson to answer each question.

1. Give an example from your classroom of three collinear points.

2. Make use of the fact that endpoint is a compound of end and point and name

the endpoint of  ST .

S E E E X A M P L E 1

p. 6

Use the figure to name each of the following.

3. five points

4. two lines

5. two planes

6. point on BD 

S E E E X A M P L E 2

p. 7

Draw and label each of the following.

7. a segment with endpoints M and N

8. a ray with endpoint F that passes through G

S E E E X A M P L E 3

p. 7

Use the figure to name each of the following.

9. a line that contains A and C

10. a plane that contains A, D, and C

S E E E X A M P L E 4

p. 8

Sketch a figure that shows each of the following.

11. three coplanar lines that intersect in a common point

12. two lines that do not intersect

PRACTICE AND PROBLEM SOLVING

For See

Exercises Example

Independent Practice Use the figure to name each of the following.

13. three collinear points

14. four coplanar points

15. a plane containing E

Draw and label each of the following.

16. a line containing X and Y

17. a pair of opposite rays that both contain R

Use the figure to name each of the following.

18. two points and a line that lie in plane T

19. two planes that contain 

Sketch a figure that shows each of the following.

20. a line that intersects two nonintersecting planes

21. three coplanar lines that intersect in three

different points

KEYWORD: MG7 1-

KEYWORD: MG7 Parent

Skills Practice p. S
Application Practice p. S

Extra Practice

Possible answer: the intersection of 2 floor tiles

S

A, B, C, D, E

Possible answer: AC , BD

Possible answer: ABC and N

Possible answer: B, C, or D

Possible answer:

AB

Possible answer: plane ABD

B, E, A

Possible answer:

B, C, D, E

Possible answer: plane ABC

Possible answer: G, J, and 

Possible answer: planes T and S

M N

F G

A B

C D

X

Y

R

R

S

ge07se_c01_0006_0011.indd 9 12/2/05 7:08:05 PM

Lesson 1-1 9

Exercises Exercises

1-

Assignment Guide

Assign Guided Practice exercises

as necessary.

If you finished Examples 1–

Basic 13–17, 33

Average 13–17, 33, 36, 43

Advanced 13–17, 33, 34, 36,

If you finished Examples 1–

Basic 13–28, 31–33, 39–42,

Average 13–28, 30–33, 35–43,

Advanced 14–28 even, 29–

Homework Quick Check

Quickly check key concepts.

Exercises: 14–20 even, 24, 26,

Communicating Math In

Exercises 3–6, students

sometimes forget to place

a symbol above the letters that are

used to name lines, segments, and

rays. Remind students that two let-

ters without a symbol represent

a distance.

KEYWORD: MG7 Resources

10 Chapter 1 Foundations for Geometry

Draw each of the following.

23. plane H containing two lines that intersect at M

24.  ST  intersecting plane M at R

Use the figure to name each of the following.

25. the intersection of  TV  and US 

26. the intersection of US  and plane R

27. the intersection of

TU and

UV

Write the postulate that justifies each statement.

28. The line connecting two dots on a sheet of paper lies on the same sheet of paper as

the dots.

29. If two ants are walking in straight lines but in different directions, their paths cannot

cross more than once.

30. Critical Thinking Is it possible to draw three points that are noncoplanar? Explain.

Tell whether each statement is sometimes, always, or never true. Support your

answer with a sketch.

31. If two planes intersect, they intersect in a straight line.

32. If two lines intersect, they intersect at two different points.

33.  AB  is another name for BA .

34. If two rays share a common endpoint, then they form a line.

35. Art Pointillism is a technique in which tiny dots of

complementary colors are combined to form a picture.

Which postulate ensures that a line connecting two of

these points also lies in the plane containing the points?

36. Probability Three of the labeled

points are chosen at random.

What is the probability that

they are collinear?

37. Campers often use a cooking stove with three legs.

Which postulate explains why they might prefer this

design to a stove that has four legs?

38. Write About It Explain why three coplanar lines may

have zero, one, two, or three points of intersection.

Support your answer with a sketch.

© 2004 Artists’ Rights Society (ARS), New York/ADAGP,Paris/Reunion des Musees Nationaux/Art Resource, NY/Detail

22. This problem will prepare you for the

Multi-Step Test Prep on page 34. Name an

object at the archaeological site shown that

is represented by each of the following.

a. a point

b. a segment

c. a plane

U

22. Possible

answers:

a. tip of a stake

b. string

c. grid formed

by string

28. If 2 pts. lie in

a plane, then the

line containing

those pts. lies

in the plane.

If 2 lines intersect, then they intersect in exactly 1 pt.

U

A

N

A

S

35. Post. 1-1-

_^1

U

30. It is not

possible. By

Post. 1-1-2, any

3 noncollinear pts.

are contained in

a unique plane.

If the 3 pts. are

collinear, they

are contained in

infinitely many

planes. In either

case, the 3 pts.

will be coplanar.

M

S A N

Post. 1-1-

ge07se_c01_0006_0011.indd 10 4/27/06 11:59:35 AM

10 Chapter 1

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1-1 PRACTICE C

1-1 PRACTICE B

1-1 PRACTICE A

Exercise 22 involves

identifying geometric

shapes at an archae-

ological site. This exercise prepares

students for the Multi-Step Test Prep

on page 34.

Visual For Exercise 36,

have students make an

organized list of all the

combinations of three points that

could be chosen and then select

those that are collinear.

Answers

R

S

T

A B

38. Lines may not

intersect: 0 pts.

of intersection.

All 3 lines may

intersect in 1 pt.

Two of the lines

may not intersect,

but they might each

intersect a third line.

Each line may

intersect each of

the other lines.

12 Chapter 1 Foundations for Geometry

1-

Use with Lesson 1-

Activity

1 Construct a segment and label its endpoints A and C.

2 Create point B on

AC.

3 Measure the distances from A to B and from B to C.

Use the Calculate tool to calculate the sum of AB

and BC.

4 Measure the length of

AC. What do you notice

about this length compared with the measurements

found in Step 3?

5 Drag point B along

AC. Drag one of the endpoints

of

AC. What relationships do you think are true

about the three measurements?

6 Construct the midpoint of

AC and label it M.

7 Measure

AM and

MC. What relationships do you

think are true about the lengths of

AC ,

AM , and

MC?

Use the Calculate tool to confirm your findings.

8 How many midpoints of

AC exist?

Try This

1. Repeat the activity with a new segment. Drag each of the points in your figure

(the endpoints, the point on the segment, and the midpoint). Write down any

relationships you observe about the measurements.

2. Create a point D not on

AC. Measure

AD ,

DC , and

AC. Does AD + DC = AC?

What do you think has to be true about D for the relationship to always be true?

Explore Properties

Associated with Points

The two endpoints of a segment determine its length. Other points on the

segment are between the endpoints. Only one of these points is the midpoint

of the segment. In this lab, you will use geometry software to measure

lengths of segments and explore properties of points on segments.

KEYWORD: MG7 Lab

NY Performance

Indicators

G.RP.3, G.R.

Check students’ work.

No; D must be between A and C.

ge07se_c01_0012.indd 1 11/23/06 1:24:18 PM

12 Chapter 1

New York Performance

Indicators

Process

G.RP.3 Investigate and evaluate

conjectures in mathematical terms,

using mathematical strategies to reach

a conclusion

G.R.1 Use physical objects, diagrams,

charts, tables, graphs, symbols,

equations, or objects created using

technology as representations of

mathematical concepts

Pacing:

Traditional

__ 1

day

Block

__ 1

day

Objective: Use geometry

software to measure distances and

explore properties of points on

segments.

Materials: geometry software

G

I

D

@<I

Online Edition

TechKeys

Countdown to

Testing Week 1

Resources

Technology Lab Activities

1-2 Lab Recording Sheet

Teach

Discuss

Emphasize that there are infinitely

many points on a line segment

between its endpoints, but only one

of these points is the midpoint.

Close

Key Concept

When three points A , B , and C are

collinear, then AB + BC = AC. The

midpoint of a segment is equidistant

from each endpoint.

Assessment

Journal Have students summarize

how they determine, given three col-

linear points, if the point between

the endpoints is the midpoint. Then

have them support their answer with

a sketch.

To introduce the concept of

midpoint, I like to tell the fol-

lowing riddle to the class.

Q: A hunter walks into the

woods and keeps walking

in the same direction. At

what point does the hunter

begin to leave the woods?

A: The midpoint.

Then I can explain to students

that once the hunter is half-

way through the woods, she is

as close to the end as to the

beginning. After passing the

midpoint, the hunter is going

out instead of in. This helps

students remember that the

midpoint is not just any point

between the endpoints, but

exactly one point in the middle.

Teresa Salas

Corpus Christi, TX

Teacher to Teacher

Organizer

Use with Lesson 1-

1- 2 Measuring and Constructing Segments 13

Why learn this?

You can measure a segment to calculate the

distance between two locations. Maps of a

race are used to show the distance between

stations on the course. (See Example 4.)

A ruler can be used to measure the distance between

two points. A point corresponds to one and

only one number on the ruler. This number

is called a coordinate. The following

postulate summarizes this concept.

The points on a line can be put

 CM      

into a one-to-one correspondence

with the real numbers.

Postulate 1-2-1 Ruler Postulate

The distance between any two points is the absolute value of the difference

of the coordinates. If the coordinates of points A and B are a and b , then the

distance between A and B is  a - b ^ or  b - a . The distance between A and B

is also called the length of

AB , or AB.

 Ê  Ê ] >Ê  ÊL ] Ê  Ê ] LÊ  Ê> ]

> L

E X A M P L E 1 Finding the Length of a Segment

{°x

 {  Î  Ó  £ ä £ Ó Î { x

Find each length.

A DC B EF

DC = 4.5 - 2  EF = - 4 - (- 1 )

= 2.5^ = - 4 + 1 

Find each length.

 Ó

£ÊÊ

£

pÊ Ê

Ó

ÊÊ

1a. XY  Î  £ ä £ Ó Î { x È

1b. XZ

Congruent segments are segments that have

/ˆVŽÊ“>ÀŽÃ

the same length. In the diagram, PQ = RS , so you

can write

_

PQ 

_

RS. This is read as “segment PQ

is congruent to segment RS .” Tick marks are

used in a figure to show congruent segments.

Objectives

Use length and midpoint

of a segment.

Construct midpoints and

congruent segments.

Vocabulary

coordinate

distance

length

congruent segments

construction

between

midpoint

bisect

segment bisector

PQ represents a

number, while

_

PQ

represents a geometric

figure. Be sure to

use equality for

numbers ( PQ = RS )

and congruence for

figures (

_

PQ 

_

RS ).

1-

Measuring and

Constructing Segments

NY Performance

Indicators

G.PS.5 Choose an effective

approach to solve a problem

from a variety of strategies

(numeric, graphic, algebraic).

Also, G.RP.2.

_ 1

_^1

ge07se_c01_0013_0019.indd 1 11/23/06 1:25:08 PM

Lesson 1-2 13

1-2 Organizer

Pacing: Traditional

(^1) __

day

Block

__^1

day

Objectives: Use length and

midpoint of a segment.

Construct midpoints and congruent

segments.

Geometry Lab

In Geometry Lab Activities

G

I

D

@<I

Online Edition

Tutorial Videos

Countdown to

Testing Week 1

Warm Up

Simplify.

1. 7 - (- 3 )^ 10 2. - 1 - (- 13 )^ 12 3.- 7 - 1 ^8

Solve each equation.

4. 2 x + 3 = 9 x - 11 2

5. 3 x = 4 x - 5 5

6. How many real numbers are

there between

__^1

and

__^3

infinitely many

Also available on transparency

Carpenter 1: Why did you leave your

tape measure in the truck?

Carpenter 2: Because we’re entering

a construction zone.

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Motivate

Show students a road map. Ask them to locate a

place that is midway between two other places.

Ask questions about distance between locations

on a straight road. “Suppose you are driving to a

relative’s house. The only place to stop for food is

75 miles from home, and it is

__ 1

of the total trip.

How far from the food stop does your relative

live?” 150 mi

Introduce

1

Explorations and answers are provided in the

Explorations binder.

New York Performance

Indicators

Process

G.PS.5 Choose an effective approach

to solve a problem from a variety of

strategies (numeric, graphic, algebraic)

G.RP.2 Recognize and verify, where

appropriate, geometric relationships

of perpendicularity, parallelism,

congruence, and similarity, using

algebraic strategies