chapter 11 resource mastersmrsstuckeysmathclass.weebly.com/.../geom_ch11_answers.pdf · 2019. 11....

Chapter 11Resource Masters

Geometry

Reading to Learn MathematicsVocabulary Builder

NAME ______________________________________________ DATE ____________ PERIOD _____

1111

© Glencoe/McGraw-Hill vii Glencoe Geometry

Voca

bula

ry B

uild

erThis is an alphabetical list of the key vocabulary terms you will learn in Chapter 11. As you study the chapter, complete each term’s definition or description.Remember to add the page number where you found the term. Add these pages toyour Geometry Study Notebook to review vocabulary at the end of the chapter.

Vocabulary Term Found on Page Definition/Description/Example

apothem

geometric probability

irregular figure

irregular polygon

(continued on the next page)

© Glencoe/McGraw-Hill viii Glencoe Geometry

Vocabulary Term Found on Page Definition/Description/Example

sector of a circle

segment of a circle

Reading to Learn MathematicsVocabulary Builder (continued)

NAME ______________________________________________ DATE ____________ PERIOD _____

1111

Learning to Read MathematicsProof Builder

NAME ______________________________________________ DATE ____________ PERIOD _____

1111

© Glencoe/McGraw-Hill ix Glencoe Geometry

Proo

f Bu

ilderThis is a list of key theorems and postulates you will learn in Chapter 11. As you

study the chapter, write each theorem or postulate in your own words. Includeillustrations as appropriate. Remember to include the page number where youfound the theorem or postulate. Add this page to your Geometry Study Notebookso you can review the theorems and postulates at the end of the chapter.

Theorem or Postulate Found on Page Description/Illustration/Abbreviation

Postulate 11.1

Postulate 11.2

Postulate 11.3Area Probability Postulate

Skills PracticeArea of Parallelograms

NAME ______________________________________________ DATE ____________ PERIOD _____

11-111-1

© Glencoe/McGraw-Hill 613 Glencoe Geometry

Less

on

11-

1

Find the perimeter and area of each parallelogram. Round to the nearest tenth ifnecessary.

1. 2.

3. 4.

5. 6.

Find the area of each figure.

7. 8.

COORDINATE GEOMETRY Given the coordinates of the vertices of a quadrilateral,determine whether it is a square, a rectangle, or a parallelogram. Then find thearea of the quadrilateral.

9. A(!4, 2), B(!1, 2), C(!1, !1), 10. P(!3, 3), Q(1, 3), R(1, !3),D(!4, !1) S(!3, !3)

11. D(!5, 1), E(7, 1), F(4, !4), 12. R(2, 3), S(4, 10), T(12, 10),G(!8, !4) U(10, 3)

8

222

2 2

2

263

3

4

6

6

1

1

1

1122

22

1

18.5 km

9 km

3.4 m

26 in.

22 in.

45!

14 yd

7 yd45!

5.5 ft

4 ft

60!

20 cm

30 cm60!


Find the perimeter and area of each parallelogram. Round to the nearest tenth ifnecessary.

1. 2. 3.

Find the area of each figure.

4. 5.

COORDINATE GEOMETRY Given the coordinates of the vertices of a quadrilateral,determine whether it is a square, a rectangle, or a parallelogram. Then find thearea of the quadrilateral.

6. C(!4, !1), D(!4, 2), F(1, 2), G(1, !1) 7. W(2, 2), X(1, !2), Y(!2, !2), Z(!1, 2)

8. M(0, 4), N(4, 6), O(6, 2), P(2, 0) 9. P(!5, 2), Q(4, 2), R(5, 5), S(!4, 5)

FRAMING For Exercises 10–12, use the following information.A rectangular poster measures 42 inches by 26 inches. A frame shop fitted the poster with ahalf-inch mat border.

10. Find the area of the poster.

11. Find the area of the mat border.

12. Suppose the wall is marked where the poster will hang. The marked area includes anadditional 12-inch space around the poster and frame. Find the total wall area that hasbeen marked for the poster.

7

7 3

3 43

1

333

3

2

2

22 8

922

2

22

2

1

1

4

4

4

10 in.

45!10 cm

8 cm

45!

5 m

11 m60!

Practice Area of Parallelograms

NAME ______________________________________________ DATE ____________ PERIOD _____

11-111-1

Skills PracticeAreas of Triangles, Trapezoids, and Rhombi

NAME ______________________________________________ DATE ____________ PERIOD _____

11-211-2


Less

on

11-

2

Find the area of each figure. Round to the nearest tenth if necessary.

1. 2. 3.

Find the area of each quadrilateral given the coordinates of the vertices.

4. trapezoid WXYZ 5. rhombus HIJKW(!5, 3), X(3, 3), Y(6, !3), Z(!8, !3) H(4, !3), I(2, !7), J(0, !3), K(2, 1)

Find the missing measure for each figure.

6. Trapezoid RSTU has an area of 7. Trapezoid JKLM has an area of 935 square centimeters. Find the 7.5 square inches. Find ML.height of RSTU.

8. Triangle ABC has an area of 9. Rhombus EFGH has an area of 1050 square meters. Find the 750 square feet. If EG is 50 feet,height of !ABC. find FH.

HE

F G

A C

B

60 m

M L

J K5 in.

2 in.

55 cmR U

TS 30 cm

34 cm28 cm

21 cm

40 cm

22 in.

12 in.25 in.

4 ft 3.5 ft6 ft



1. 2.

3.

Find the area of each quadrilateral given the coordinates of the vertices.

4. trapezoid ABCD 5. rhombus LMNOA(!7, 1), B(!4, 4), C(!4, !6), L(6, 8), M(14, 4), N(6, 0),D(!7, !3) O(!2, 4)

Find the missing measure for each figure.

6. Trapezoid WXYZ has an area of 7. Triangle PRS has an area of 13.75 square meters. Find WX. 68 square yards. If the height of !PRS

is 8 yards, find the base.

DESIGN For Exercises 8 and 9, use the following information.Mr. Hagarty used 16 congruent rhombi-shaped tiles to design themidsection of the backsplash area above a kitchen sink. The length of the design is 27 inches and the total area is 108 square inches.

8. Find the area of one rhombus.

9. Find the length of each diagonal.

P S

R

Z Y

W X

3.5 m

2.5 m

37 ft 22 ft 26 ft

10 cm

3 cm6 cm3.5 cm

4 m

2.6 m1.5 m

3.2 m

Practice Areas of Triangles, Trapezoids, and Rhombi

NAME ______________________________________________ DATE ____________ PERIOD _____

11-211-2

Skills PracticeAreas of Regular Polygons and Circles

NAME ______________________________________________ DATE ____________ PERIOD _____

11-311-3


Less

on

11-

3

Find the area of each regular polygon. Round to the nearest tenth.

1. a pentagon with a perimeter of 45 feet

2. a hexagon with a side length of 4 inches

3. a nonagon with a side length of 8 meters

4. a triangle with a perimeter of 54 centimeters

Find the area of each circle. Round to the nearest tenth.

5. a circle with a radius of 6 yards

6. a circle with a diameter of 18 millimeters

Find the area of each shaded region. Assume that all polygons are regular. Roundto the nearest tenth.

7. 8.

9. 10.

5 cm4 ft

8 m

4 m

3 in.


Find the area of each regular polygon. Round to the nearest tenth.

1. a nonagon with a perimeter of 117 millimeters

2. an octagon with a perimeter of 96 yards

Find the area of each circle. Round to the nearest tenth.

3. a circle with a diameter of 26 feet

4. a circle with a circumference of 88 kilometers

Find the area of each shaded region. Assume that all polygons are regular. Roundto the nearest tenth.

5. 6.

7. 8.

DISPLAYS For Exercises 9 and 10, use the following information.A display case in a jewelry store has a base in the shape of a regular octagon. The length ofeach side of the base is 10 inches. The owners of the store plan to cover the base in blackvelvet.

9. Find the area of the base of the display case.

10. Find the number of square yards of fabric needed to cover the base.

9 m

25 ft

4.4 in.12 cm

Practice Areas of Regular Polygons and Circles

NAME ______________________________________________ DATE ____________ PERIOD _____

11-311-3

Skills PracticeAreas of Irregular Figures

NAME ______________________________________________ DATE ____________ PERIOD _____

11-411-4


Less

on

11-

4


1. 2.

3. 4.

5. 6.

7. 8.

x

y

O

D(–2, –2)

G(4, 1)

H(2, –2)

E(–2, 4) F(2, 4)

x

y

O L(6, 0)

M(1, –3)

J(1, 4) K(5, 4)

x

y

O

Q(3, 5)

R(6, 7)P(0, 7)

T(3, 2)

U(0, 0) S(6, 0)x

y

O

D(8, 5)

E(8, 0)

C(3, 8)

B(3, 5)

A(0, 0)

30

15

8

8

7

3

5

12

20



1. 2.

3. 4.

5. 6.

LANDSCAPING For Exercises 7 and 8, use the following information.One of the displays at a botanical garden is a koi pond with a walkway around it.The figure shows the dimensions of the pond and the walkway.

7. Find the area of the pond to the nearest tenth.

8. Find the area of the walkway to the nearest tenth.

35 ft13 ft

15 ft7 ft

x

y

O S(2, 0)

Q(2, 6)

P(–2, 3)

T(–2, 1)

R(4, 3)

x

y

O

D(2, 5)

B(–1, 3)

A(–1, 0)

C(1, 4)E(4, 4)

F(4, 0)

13

13

20

30

23

7

9

38

22

22

20

20

Practice Areas of Irregular Figures

NAME ______________________________________________ DATE ____________ PERIOD _____

11-411-4

Skills PracticeGeometric Probability

NAME ______________________________________________ DATE ____________ PERIOD _____

11-511-5


Less

on

11-

5

Find the probability that a point chosen at random lies in the shaded region.

1. 2.

Find the area of the indicated sector. Then find the probability of spinning thecolor indicated if the diameter of each spinner is 6 inches.

3. red

4. gold

5. blue

6. yellow

Find the area of the shaded region. Then find the probability that a point chosenat random is in the shaded region. Assume that all inscribed polygons are regular.

7. 8.

812

blue

blue

pink

red40!

40!30!

50!60!

70!70! red

yellow

yellow

gold

blue

bluered

gold60!

60!

60!100!

80!


Find the probability that a point chosen at random lies in the shaded region.

1. 2.

Find the area of the indicated sector. Then find the probability of spinning thecolor indicated if the diameter of the spinner is 9 meters.

3. red

4. blue

5. yellow

Find the area of the shaded region. Then find the probability that a point chosenat random is in the shaded region. Assume that all inscribed polygons are regular.

6. 7.

8. ARCHERY A target consists of four concentric rings. The radius of the center circle is 4 inches, and the circles are spaced 2 inches apart. Find the probability that an arrow shot at random by an inexperienced archer will land in a shaded region.

4 in.

2 in.

2 in.

2 in.

1711

blue

80!40!

100!85!

55!blue

red

redyellow

Practice Geometric Probability

NAME ______________________________________________ DATE ____________ PERIOD _____

11-511-5

© Glencoe/McGraw-Hill A2 Glencoe Geometry

Stu

dy

Gu

ide

and I

nte

rven

tion

Are

as o

f Par

alle

logr

ams

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

ATE

____

____

____

PE

RIO

D__

___

11-1

11-1

©G

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Lesson 11-1

Are

as o

f Pa

ralle

log

ram

sA

par

alle

logr

am is

a q

uadr

ilate

ral w

ith

both

pai

rs o

fop

posi

te s

ides

par

alle

l.A

ny s

ide

of a

par

alle

logr

am c

an b

e ca

lled

a ba

se.E

ach

base

has

aco

rres

pond

ing

alti

tud

e,an

d th

e le

ngth

of

the

alti

tude

is t

he h

eigh

tof

the

par

alle

logr

am.

The

are

a of

a p

aral

lelo

gram

is t

he p

rodu

ct o

f th

e ba

se a

nd t

he h

eigh

t.

If a

para

llelo

gram

has

an

area

of A

squa

re u

nits

, A

rea

of a

Par

alle

logr

ama

base

of b

units

, and

a h

eigh

t of h

units

, th

en A

!bh

.

The

are

a of

par

alle

logr

am

AB

CD

is C

D"

AT.

Fin

d t

he

area

of

par

alle

logr

am E

FG

H.

A!

bhA

rea

of a

par

alle

logr

am

!30

(18)

b!

30, h

!18

!54

0M

ultip

ly.

The

are

a is

540

squ

are

met

ers.

Fin

d t

he

area

of

each

par

alle

logr

am.

1.2.

3.

288

ft2

288!

3"in

22.

56 c

m2

Fin

d t

he

area

of

each

sh

aded

reg

ion

.

4.W

XY

Zan

d A

BC

Dar

e 5.

All

angl

es a

re r

ight

6.

EF

GH

and

NO

PQ

are

rect

angl

es.

angl

es.

rect

angl

es;J

KL

Mis

asq

uare

.

452

cm2

51 f

t235

1 in

2

7.T

he a

rea

of a

par

alle

logr

am is

3.3

6 sq

uare

fee

t.T

he b

ase

is 2

.8 f

eet.

If t

he m

easu

res

ofth

e ba

se a

nd h

eigh

t ar

e ea

ch d

oubl

ed,f

ind

the

area

of

the

resu

ltin

g pa

ralle

logr

am.

13.4

4 ft

2

8.A

rec

tang

le is

4 m

eter

s lo

nger

tha

n it

is w

ide.

The

are

a of

the

rec

tang

le is

252

squ

are

met

ers.

Fin

d th

e le

ngth

.18

m

30 in

.

18 in

.EF G

H

JK

NO P

QL

M

9 in

.9

in.

9 in

.12

in.

12 ft

3 ft

3 ft 3 ft

8 ft

3 ft

2 ft

6 ft

32 c

m

16 c

m

12 c

m5

cm

WX Y

Z

AB

DC

1.6

cm

1.6

cm60

!

24 in

.

16 ft

18 ft

18 m

30 m

HG

FE

h

DT

C

BA

b

Exam

ple

Exam

ple

Exer

cises

Exer

cises

©G

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Para

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ms

on

th

e C

oo

rdin

ate

Plan

eTo

fin

d th

e ar

ea o

f a

quad

rila

tera

l on

the

coor

dina

te p

lane

,use

the

Slo

pe F

orm

ula,

the

Dis

tanc

e Fo

rmul

a,an

d pr

oper

ties

of

para

llelo

gram

s,re

ctan

gles

,squ

ares

,and

rho

mbi

.

Th

e ve

rtic

es o

f a

quad

rila

tera

l ar

e A

(#2,

2),

B(4

,2),

C(5

,#1)

,an

d D

(#1,

#1)

.

a.D

eter

min

e w

het

her

th

e qu

adri

late

ral

is a

squ

are

,a

rect

an

gle,

or a

pa

rall

elog

ram

.G

raph

the

qua

drila

tera

l.T

hen

dete

rmin

e th

e sl

ope

of e

ach

side

.

slop

e of

A !B!

!$ 4

2 ## (#

2 2)$

or 0

slop

e of

C !D!

!$#

#11#

#(#51)

$or

0

slop

e A !

D!!$ #2 2# #

(# (#1 1) )

$or

#3

slop

e B !

C!!

$# 51 ##42

$or

#3

Opp

osit

e si

des

have

the

sam

e sl

ope.

The

slo

pes

of c

onse

cuti

ve s

ides

are

not

neg

ativ

ere

cipr

ocal

s of

eac

h ot

her,

so c

onse

cuti

ve s

ides

are

not

per

pend

icul

ar.A

BC

Dis

apa

ralle

logr

am;i

t is

not

a r

ecta

ngle

or

a sq

uare

.

b.F

ind

th

e ar

ea o

f A

BC

D.

Fro

m t

he g

raph

,the

hei

ght

of t

he p

aral

lelo

gram

is 3

uni

ts a

nd A

B!

| 4 #

(#2)

| !6.

A!

bhA

rea

of a

par

alle

logr

am

!6(

3)b

!6,

h!

3

!18

uni

ts2

Mul

tiply

.

Giv

en t

he

coor

din

ates

of

the

vert

ices

of

a qu

adri

late

ral,

det

erm

ine

wh

eth

er t

he

quad

rila

tera

l is

a s

qua

re,a

rec

tan

gle,

or a

pa

rall

elog

ram

.Th

en f

ind

th

e ar

ea.

1.A

(#1,

2),B

(3,2

),C

(3,#

2),a

nd D

(#1,

#2)

squa

re;1

6 un

its2

2.R

(#1,

2),S

(5,0

),T

(4,#

3),a

nd U

(#2,

#1)

rect

angl

e;20

uni

ts2

3.C

(#2,

3),D

(3,3

),E

(5,0

),an

d F

(0,0

)pa

ralle

logr

am;1

5 un

its2

4.A

(#2,

#2)

,B(0

,2),

C(4

,0),

and

D(2

,#4)

squa

re;2

0 un

its2

5.M

(2,3

),N

(4,#

1),P

(#2,

#1)

,and

R(#

4,3)

para

llelo

gram

;24

units

2

6.D

(2,1

),E

(2,#

4),F

(#1,

#4)

,and

G(#

1,1)

rect

angl

e;15

uni

ts2

x

y

OD

C

BA

Stu

dy

Gu

ide

and I

nte

rven

tion

(con

tinu

ed)

Are

as o

f Par

alle

logr

ams

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

ATE

____

____

____

PE

RIO

D__

___

11-1

11-1

Exam

ple

Exam

ple

Exer

cises

Exer

cises

Answers (Lesson 11-1)


An

swer

s

Skil

ls P

ract

ice

Are

a of

Par

alle

logr

ams

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

ATE

____

____

____

PE

RIO

D__

___

11-1

11-1

©G

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etry

Lesson 11-1

Fin

d t

he

per

imet

er a

nd

are

a of

eac

h p

aral

lelo

gram

.Rou

nd

to

the

nea

rest

ten

th i

fn

eces

sary

.

1.2.

100

cm,5

19.6

cm

219

ft,

19.1

ft2

3.4.

42 y

d,69

.3 y

d296

in.,

404.

5 in

2

5.6.

13.6

m,1

1.6

m2

55 k

m,1

66.5

km

2

Fin

d t

he

area

of

each

fig

ure

.

7.8.

14 u

nits

258

uni

ts2

CO

OR

DIN

ATE

GEO

MET

RYG

iven

th

e co

ord

inat

es o

f th

e ve

rtic

es o

f a

quad

rila

tera

l,d

eter

min

e w

het

her

it

is a

squ

are

,a r

ecta

ngl

e,or

a p

ara

llel

ogra

m.T

hen

fin

d t

he

area

of

the

quad

rila

tera

l.

9.A

(#4,

2),B

(#1,

2),C

(#1,

#1)

,10

.P(#

3,3)

,Q(1

,3),

R(1

,#3)

,D

(#4,

#1)

S(#

3,#

3)sq

uare

,9 u

nits

2re

ctan

gle,

24 u

nits

2

11.D

(#5,

1),E

(7,1

),F

(4,#

4),

12.R

(2,3

),S

(4,1

0),T

(12,

10),

G(#

8,#

4)U

(10,

3)pa

ralle

logr

am,6

0 un

its2

para

llelo

gram

,56

units

2

8 22

2222

26

33

4

66

1 1

1

11

2 22 2

1

18.5

km

9 km

3.4

m

26 in

.

22 in

.

45!

14 y

d

7 yd

45!

5.5

ft

4 ft 60

!

20 c

m

30 c

m60

!

©G

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Fin

d t

he

per

imet

er a

nd

are

a of

eac

h p

aral

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gram

.Rou

nd

to

the

nea

rest

ten

th i

fn

eces

sary

.

1.2.

3.

32 m

,47.

6 m

236

cm

,56.

6 cm

234

.1 in

.,50

in2

Fin

d t

he

area

of

each

fig

ure

.

4.5.

44 u

nits

265

uni

ts2

CO

OR

DIN

ATE

GEO

MET

RYG

iven

th

e co

ord

inat

es o

f th

e ve

rtic

es o

f a

quad

rila

tera

l,d

eter

min

e w

het

her

it

is a

squ

are

,a r

ecta

ngl

e,or

a p

ara

llel

ogra

m.T

hen

fin

d t

he

area

of

the

quad

rila

tera

l.

6.C

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the

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the

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mat

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es a

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diti

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11-1

11-1



Rea

din

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of P

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11-1

11-1

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Lesson 11-1

Pre-

Act

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s ar

ea r

elat

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o ga

rden

des

ign

?

Rea

d th

e in

trod

ucti

on t

o L

esso

n 11

-1 a

t th

e to

p of

pag

e 59

5 in

you

r te

xtbo

ok.

How

cou

ld y

ou d

escr

ibe

the

patt

ern

you

see

in t

he p

ictu

re o

f th

e ga

rden

so

that

som

eone

who

doe

sn’t

have

the

pic

ture

will

kno

w w

hat

it lo

oks

like?

Sam

ple

answ

er:T

here

are

squ

ares

of

gran

ite a

nd s

quar

es o

fm

oss

of t

he s

ame

size

pla

ced

in a

che

cker

boar

d de

sign

.

Rea

din

g t

he

Less

on

1.W

hich

exp

ress

ion

give

s th

e ar

ea o

f th

e pa

ralle

logr

am?

(Hin

t:T

here

can

be

mor

e th

an o

ne c

orre

ct r

espo

nse.

)B

,D,E

,GA

.ab

B.c

bC

.ed

D.a

fE

.ce

F.cd

G.d

fH

.bf

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efer

to

the

figu

re.D

eter

min

e w

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ach

stat

emen

t

is t

rue

or f

alse

.If

the

stat

emen

t is

fal

se,e

xpla

in w

hy.

a.A!

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an

alti

tude

of

the

para

llelo

gram

.Fa

lse;

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is n

otpe

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ide

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he p

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.

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ase

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AB

CD

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c.T

he p

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of A

BC

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E!

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lse;

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ppos

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he 3

0°an

gle

in a

30°

-60°

-90°

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ngle

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BE

#$1 2$ x

or $x 2$ .

f.T

he a

rea

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BC

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nce

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area

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ou

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ay t

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w f

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ula

in g

eom

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o re

late

it t

o a

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you

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you

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a fo

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ea o

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rect

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hel

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ure

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ple

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d th

e ar

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f a

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angl

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u m

ultip

ly t

he le

ngth

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tw

o se

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ts t

hat

are

perp

endi

cula

r to

eac

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her.

To f

ind

the

area

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a pa

ralle

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ou d

o th

e sa

me

thin

g,bu

t th

e he

ight

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ot n

eces

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sid

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d

AE

DFC

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inte

rest

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lts

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g th

e fo

rmul

a yo

u ha

ve p

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d fo

r th

e ar

ea o

f a

para

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draw

ing

auxi

liary

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for

m c

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reg

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.Con

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ppa

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the

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kis

the

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side

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fig

ure,

whi

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how

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num

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uxili

ary

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rs a

dded

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wha

t yo

u kn

ow a

bout

per

pend

icul

ar li

nes,

para

llel l

ines

,and

co

ngru

ent

tria

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s to

ans

wer

the

fol

low

ing.

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hat

kind

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figu

re is

DB

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rect

angl

e

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you

mov

ed !

AF

Bto

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low

er-l

eft

end

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igur

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ould

it f

it p

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ctly

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top

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lain

yo

ur a

nsw

er.

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HA

) an

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ince

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angl

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EC

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.

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hich

tw

o tr

iang

ular

pie

ces

of "

AB

CD

are

cong

ruen

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?

!D

AF

and

!B

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4.T

he a

rea

of "

AB

CD

is t

he s

ame

as t

hat

of f

igur

e D

BH

G,

sinc

e th

e pi

eces

of "

AB

CD

can

be r

earr

ange

d to

for

m

DB

HG

.Exp

ress

the

are

a of

"A

BC

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ter

ms

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mea

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and

d.

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BC

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DC

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ME

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11-1

11-1



An

swer

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Stu

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11-2

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tri

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an

area

of A

squa

re u

nits

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ase

of b

units

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ngth

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the

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rig

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rian

gle

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eter

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36 m

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tenu

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f 15

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g of

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met

ers.

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d th

e ar

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le.

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2

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um o

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es.T

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rho

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f th

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diag

onal

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trap

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are

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Asq

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ts, b

ases

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2.

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he

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vert

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11-2

11-2

Exam

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Skil

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1.2.

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he b

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the

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Pra

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ME

____

____

____

____

____

____

____

____

____

____

____

__D

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____

____

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___

11-2

11-2



An

swer

s

Rea

din

g t

o L

earn

Math

emati

csA

reas

of T

rian

gles

,Tra

pezo

ids,

and

Rho

mbi

NA

ME

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ATE

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RIO

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11-2

11-2

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Lesson 11-2

Pre-

Act

ivit

yH

ow i

s th

e ar

ea o

f a

tria

ngl

e re

late

d t

o be

ach

um

brel

las?

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d th

e in

trod

ucti

on t

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esso

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-2 a

t th

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on

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atch

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plai

n yo

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r ex

plan

atio

ns,s

ampl

e an

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s ar

e gi

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rea

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alf

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prod

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agon

als.

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ays;

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bus,

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ou c

an u

se t

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hom

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form

ula.

b.T

he a

rea

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tri

angl

e is

hal

f th

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side

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omet

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true

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r a

righ

t tr

iang

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c.Yo

u ca

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d th

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mul

tipl

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bas

e ti

mes

hei

ght.

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par

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o yo

u ca

n us

e th

e pa

ralle

logr

am fo

rmul

a.If

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leng

th o

f a r

ecta

ngle

is u

sed

as th

e ba

se,t

hen

the

wid

th is

the

heig

ht.

d.Yo

u ca

n fi

nd t

he a

rea

of a

rec

tang

le b

y m

ulti

plyi

ng t

he le

ngth

s of

any

tw

o of

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side

s.S

omet

imes

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s is

tru

e on

ly fo

r a

squa

re.O

ther

wis

e,yo

u m

ust

use

two

cons

ecut

ive

side

s,no

t an

y tw

o si

des.

e.T

he a

rea

of a

tra

pezo

id is

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pro

duct

of

its

heig

ht a

nd t

he s

um o

f th

e ba

ses.

Nev

er;

the

area

is o

ne-h

alf

the

prod

uct

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s he

ight

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the

sum

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the

base

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th o

f a

side

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qual

to

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the

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duct

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diag

onal

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lway

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he fo

rmul

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r a

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t gi

ve t

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ame

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ver

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ula

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ate

it in

wor

ds.W

rite

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hort

sent

ence

tha

t te

lls h

ow t

o fi

nd t

he a

rea

of a

tra

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id in

a w

ay t

hat

is e

asy

to r

emem

ber.

Sam

ple

answ

er:A

vera

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he le

ngth

s of

the

bas

es a

nd m

ultip

ly b

y th

ehe

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.

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11-2

11-2



Stu

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11-3

11-3

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11-3

11-3

Exam

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11-3

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the

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____

____

____

____

____

____

____

____

____

____

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ATE

____

____

____

PE

RIO

D__

___

11-3

11-3



Rea

din

g t

o L

earn

Math

emati

csA

reas

of R

egul

ar P

olyg

ons

and

Cir

cles

NA

ME

____

____

____

____

____

____

____

____

____

____

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ATE

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RIO

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11-3

11-3

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Lesson 11-3

Pre-

Act

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an y

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ind

th

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ea o

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ygon

?

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d th

e in

trod

ucti

on t

o L

esso

n 11

-3 a

t th

e to

p of

pag

e 61

0 in

you

r te

xtbo

ok.

How

can

you

fin

d th

e ar

ea o

f a

regu

lar

hexa

gon

wit

hout

a n

ew a

rea

form

ula?

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ple

answ

er:D

ivid

e th

e he

xago

n in

to s

ix c

ongr

uent

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late

ral t

rian

gles

.Use

pro

pert

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of t

he 3

0°-6

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leto

fin

d th

e ar

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n th

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ple

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BC

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ple

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gle

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___

11-4

11-4



Stu

dy

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ide

and I

nte

rven

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met

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babi

lity

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ME

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Prob

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tyT

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par

ticu

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rea

of t

he p

art

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ME

____

____

____

____

____

____

____

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11-5

11-5

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11-5

11-5



Rea

din

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o L

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Math

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bilit

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NA

ME

____

____

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11-5

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Pre-

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an g

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trod

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n 11

-5 a

t th

e to

p of

pag

e 62

2 in

you

r te

xtbo

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prob

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on

1.E

xpla

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renc

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twee

n a

sect

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nd a

seg

men

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a c

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ampl

ean

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r of

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nd it

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terc

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seg

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rc a

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11-5

11-5


chapter 11 resource mastersmrsstuckeysmathclass.weebly.com/.../geom_ch11_answers.pdf · 2019. 11....

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