answers (lesson 7-1) · pdf fileanswers name ... lesson 7-1 f ind the geometric mean between...

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© Glencoe/McGraw-Hill A3 Glencoe Geometry Answers Skills Practice Geometric Mean NAME ______________________________________________ DATE ____________ PERIOD _____ 7-1 7-1 © Glencoe/McGraw-Hill 353 Glencoe Geometry Lesson 7-1 Find the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8 2. 9 and 36 3. 4 and 7 4 18 28 5.3 4. 5 and 10 5. 22 and 52 6. 35 and 55 50 7.1 20 4.5 75 8.7 Find the measure of each altitude. State exact answers and answers to the nearest tenth. 7. 8. 14 3.7 24 4.9 9. 10. 18 4.2 6 Find x and y. 11. 12. 6; 108 10.4 40 6.3; 56 7.5 13. 14. 60 7.7; 285 16.9 12.5; 29 5.4 2 5 y x 15 4 y x 10 4 y x 3 9 y x R T S U 4.5 8 G E H F 2 9 L M N P 2 12 C D B A 2 7 © Glencoe/McGraw-Hill 354 Glencoe Geometry Find the geometric mean between each pair of numbers to the nearest tenth. 1. 8 and 12 2. 37 and 67 3. 4 5 and 2 96 9.8 126 11.2 8 5 1.3 Find the measure of each altitude. State exact answers and answers to the nearest tenth. 4. 5. 60 7.7 102 10.1 Find x, y, and z. 6. 7. 184 13.6; 248 15.7; 114 10.7; 150 12.2; 713 26.7 475 21.8 8. 9. 4.5; 13 3.6; 6.5 15; 5; 300 17.3 10. CIVIL ENGINEERING An airport, a factory, and a shopping center are at the vertices of a right triangle formed by three highways. The airport and factory are 6.0 miles apart. Their distances from the shopping center are 3.6 miles and 4.8 miles, respectively. A service road will be constructed from the shopping center to the highway that connects the airport and factory. What is the shortest possible length for the service road? Round to the nearest hundredth. 2.88 mi x y 10 z 20 x y 2 3 z z x y 6 25 23 z x y 8 17 6 K L J M 12 5 U T A V Practice (Average) Geometric Mean NAME ______________________________________________ DATE ____________ PERIOD _____ 7-1 7-1 Answers (Lesson 7-1)

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Page 1: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

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7-1

7-1

Answers (Lesson 7-1)

Page 2: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill 354 Glencoe Geometry

Find the geometric mean between each pair of numbers to the nearest tenth.

1. 8 and 12 2. 3�7� and 6�7� 3. �45� and 2

Find the measure of each altitude. State exact answers and answers to the nearesttenth.

4. 5.

Find x, y, and z.

6. 7.

8. 9.

10. CIVIL ENGINEERING An airport, a factory, and a shopping center are at the vertices of aright triangle formed by three highways. The airport and factory are 6.0 miles apart. Theirdistances from the shopping center are 3.6 miles and 4.8 miles, respectively. A service roadwill be constructed from the shopping center to the highway that connects the airport andfactory. What is the shortest possible length for the service road? Round to the nearesthundredth.

x y

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NAME ______________________________________________ DATE ____________ PERIOD _____

7-17-1

Page 3: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

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7-2

7-2

Answers (Lesson 7-2)

Page 4: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill 360 Glencoe Geometry

Find x.

1. 2. 3.

4. 5. 6.

Determine whether �GHI is a right triangle for the given vertices. Explain.

7. G(2, 7), H(3, 6), I(�4, �1) 8. G(�6, 2), H(1, 12), I(�2, 1)

9. G(�2, 1), H(3, �1), I(�4, �4) 10. G(�2, 4), H(4, 1), I(�1, �9)

Determine whether each set of measures can be the measures of the sides of aright triangle. Then state whether they form a Pythagorean triple.

11. 9, 40, 41 12. 7, 28, 29 13. 24, 32, 40

14. �95�, �

152�, 3 15. �

13�, , 1 16. , , �

47�

17. CONSTRUCTION The bottom end of a ramp at a warehouse is 10 feet from the base of the main dock and is 11 feet long. How high is the dock?

11 ft?

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Practice The Pythagorean Theorem and Its Converse

NAME ______________________________________________ DATE ____________ PERIOD _____

7-27-2

Page 5: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

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ENS

On

e of

th

e di

spla

ys a

t a

bota

nic

al g

arde

n

is a

n h

erb

gard

en p

lan

ted

in t

he

shap

e of

a s

quar

e.T

he

squ

are

mea

sure

s 6

yard

s on

eac

h s

ide.

Vis

itor

s ca

n v

iew

th

e h

erbs

fro

m a

diag

onal

pat

hw

ay t

hro

ugh

th

e ga

rden

.How

lon

g is

th

e pa

thw

ay?

6�2�

yd o

r ab

ou

t 8.

48 y

d

6 yd

6 yd

6 yd

6 yd

bA

B C

D

a

x

y60

30�

c

11�

2��

2

x

45�

11

y60

�3.

5

xy

x�y

28

9�2�

�2

9�2�

�2

y

x

30�

26y

x

2560�

yx

45�

9Pra

ctic

e (

Ave

rag

e)

Sp

ecia

l Rig

ht T

rian

gle

s

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

7-3

Answers (Lesson 7-3)

Page 6: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill 366 Glencoe Geometry

Find x and y.

1. 2. 3.

4. 5. 6.

For Exercises 7–9, use the figure at the right.

7. If a � 4�3�, find b and c.

8. If x � 3�3�, find a and CD.

9. If a � 4, find CD, b, and y.

10. The perimeter of an equilateral triangle is 39 centimeters. Find the length of an altitudeof the triangle.

11. �MIP is a 30°-60°-90° triangle with right angle at I, and I�P� the longer leg. Find thecoordinates of M in Quadrant I for I(3, 3) and P(12, 3).

12. �TJK is a 45°-45°-90° triangle with right angle at J. Find the coordinates of T inQuadrant II for J(�2, �3) and K(3, �3).

13. BOTANICAL GARDENS One of the displays at a botanical garden is an herb garden planted in the shape of a square. The square measures 6 yards on each side. Visitors can view the herbs from adiagonal pathway through the garden. How long is the pathway?

6 yd 6 yd

6 yd

6 yd

bA

B

C

D

a

x

y60�

30�

c

x

45�

11

y60�3.5

xy

x�

y 28

y

x

30�

26y

x

25

60�

yx

45�9

Practice Special Right Triangles

NAME ______________________________________________ DATE ____________ PERIOD _____

7-37-3

Page 7: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

Skills PracticeSpecial Right Triangles

NAME ______________________________________________ DATE ____________ PERIOD _____

7-37-3

© Glencoe/McGraw-Hill 365 Glencoe Geometry

Less

on

7-3

Find x and y.

1. 2. 3.

4. 5. 6.

For Exercises 7–9, use the figure at the right.

7. If a � 11, find b and c.

8. If b � 15, find a and c.

9. If c � 9, find a and b.

For Exercises 10 and 11, use the figure at the right.

10. The perimeter of the square is 30 inches. Find the length of B�C�.

11. Find the length of the diagonal B�D�.

12. The perimeter of the equilateral triangle is 60 meters. Find the length of an altitude.

13. �GEC is a 30°-60°-90° triangle with right angle at E, and E�C� is the longer leg. Find the coordinates of G in Quadrant I for E(1, 1) and C(4, 1).

E

FGD 60�

A B

CD 45�

bA

B

C

ac

60�

30�

y

x�

13

1313

13

y

x60�

16

y

x

45� 8

y

x

45�

12

y

x

30�

32

y

x60� 24

Page 8: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill A12 Glencoe Geometry

Skil

ls P

ract

ice

Trig

on

om

etry

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4

©G

lenc

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w-H

ill37

1G

lenc

oe G

eom

etry

Lesson 7-4

Use

�R

ST

to f

ind

sin

R,c

os R

,tan

R,s

in S

,cos

S,a

nd

tan

S.

Exp

ress

eac

h r

atio

as

a fr

acti

on a

nd

as

a d

ecim

al t

o th

e n

eare

st h

un

dre

dth

.

1.r

�16

,s�

30,t

�34

2.r

�10

,s�

24,t

�26

sin

R�

�1 36 4��

0.47

;si

n R

��1 20 6�

�0.

38;

cos

R�

�3 30 4��

0.88

;co

s R

��2 24 6�

�0.

92;

tan

R�

�1 36 0��

0.53

;ta

n R

��1 20 4�

�0.

42;

sin

S�

�3 30 4��

0.88

;si

n S

��2 24 6�

�0.

92;

cos

S�

�1 36 4��

0.47

;co

s S

��1 20 6�

�0.

38;

tan

S�

�3 10 6��

1.88

tan

S�

�2 14 0��

2.4

Use

a c

alcu

lato

r to

fin

d e

ach

val

ue.

Rou

nd

to

the

nea

rest

ten

-th

ousa

nd

th.

3.si

n 5

0.08

724.

tan

23

0.42

455.

cos

610.

4848

6.si

n 7

5.8

0.96

947.

tan

17.

30.

3115

8.co

s 52

.90.

6032

Use

th

e fi

gure

to

fin

d e

ach

tri

gon

omet

ric

rati

o.E

xpre

ss

answ

ers

as a

fra

ctio

n a

nd

as

a d

ecim

al r

oun

ded

to

the

nea

rest

ten

-th

ousa

nd

th.

9.ta

n C

10.s

in A

11.c

os C

� 49 0��

0.22

50�4 40 1�

�0.

9756

�4 40 1��

0.97

56

Fin

d t

he

mea

sure

of

each

acu

te a

ngl

e to

th

e n

eare

st t

enth

of

a d

egre

e.

12.s

in B

�0.

2985

17.4

13.t

an A

�0.

4168

22.6

14.c

os R

�0.

8443

32.4

15.t

an C

�0.

3894

21.3

16.c

os B

�0.

7329

42.9

17.s

in A

�0.

1176

6.8

Fin

d x

.Rou

nd

to

the

nea

rest

ten

th.

18.

19.

20.

28.8

73.5

15.9

19

x

33�

UL

S

27

x�8

BAC

27

x�

13 BA

C

41

409

B

A

C

sR

S Trt

©G

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oe/M

cGra

w-H

ill37

2G

lenc

oe G

eom

etry

Use

�L

MN

to f

ind

sin

L,c

os L

,tan

L,s

in M

,cos

M,a

nd

tan

M.

Exp

ress

eac

h r

atio

as

a fr

acti

on a

nd

as

a d

ecim

al t

o th

e n

eare

st h

un

dre

dth

.

1.�

�15

,m�

36,n

�39

2.�

�12

,m�

12�

3�,n

�24

sin

L�

�1 35 9��

0.38

;si

n L

��1 22 4�

�0.

50;

cos

L�

�3 36 9��

0.92

;co

s L

��

0.87

;

tan

L�

�1 35 6��

0.42

;ta

n L

��

0.58

;

sin

M�

�3 36 9��

0.92

;si

n M

��

0.87

;

cos

M�

�1 35 9��

0.38

;co

s M

��1 22 4�

�0.

50;

tan

M�

�3 16 5��

2.4

tan

M�

�1.

73

Use

a c

alcu

lato

r to

fin

d e

ach

val

ue.

Rou

nd

to

the

nea

rest

ten

-th

ousa

nd

th.

3.si

n 9

2.4

0.99

914.

tan

27.

50.

5206

5.co

s 64

.80.

4258

Use

th

e fi

gure

to

fin

d e

ach

tri

gon

omet

ric

rati

o.E

xpre

ss

answ

ers

as a

fra

ctio

n a

nd

as

a d

ecim

al r

oun

ded

to

the

nea

rest

ten

-th

ousa

nd

th.

6.co

s A

7.ta

n B

8.si

n A

�0.

9487

�3 1��

3.00

00�

0.31

62

Fin

d t

he

mea

sure

of

each

acu

te a

ngl

e to

th

e n

eare

st t

enth

of

a d

egre

e.

9.si

n B

�0.

7823

51.5

10.t

an A

�0.

2356

13.3

11.c

os R

�0.

6401

50.2

Fin

d x

.Rou

nd

to

the

nea

rest

ten

th.

12.

64.4

13.

18.1

14.

24.2

15.G

EOG

RA

PHY

Die

go u

sed

a th

eodo

lite

to

map

a r

egio

n o

f la

nd

for

his

cl

ass

in g

eom

orph

olog

y.T

o de

term

ine

the

elev

atio

n o

f a

vert

ical

roc

kfo

rmat

ion

,he

mea

sure

d th

e di

stan

ce f

rom

th

e ba

se o

f th

e fo

rmat

ion

to

his

pos

itio

n a

nd

the

angl

e be

twee

n t

he

grou

nd

and

the

lin

e of

sig

ht

to

the

top

of t

he

form

atio

n.T

he

dist

ance

was

43

met

ers

and

the

angl

e w

as

36 d

egre

es.W

hat

is

the

hei

ght

of t

he

form

atio

n t

o th

e n

eare

st m

eter

?31

m

36� 43

m

41�

x

3229

x�9

23

x�

11

�10�

�10

3 �10�

�10

15

5��10

5 CA

B

12�

3��

12

12�

3��

2412� 12

�3�

12�

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24

ML

N

Pra

ctic

e (

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rag

e)

Trig

on

om

etry

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4

Answers (Lesson 7-4)

Page 9: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill A13 Glencoe Geometry

An

swer

s

Readin

g t

o L

earn

Math

em

ati

csTr

igo

no

met

ry

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4

©G

lenc

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cGra

w-H

ill37

3G

lenc

oe G

eom

etry

Lesson 7-4

Pre-

Act

ivit

yH

ow c

an s

urv

eyor

s d

eter

min

e an

gle

mea

sure

s?

Rea

d th

e in

trod

uct

ion

to

Les

son

7-4

at

the

top

of p

age

364

in y

our

text

book

.

•W

hy

is i

t im

port

ant

to d

eter

min

e th

e re

lati

ve p

osit

ion

s ac

cura

tely

in

nav

igat

ion

? (G

ive

two

poss

ible

rea

son

s.)

Sam

ple

an

swer

s:(1

) To

avo

id c

olli

sio

ns

bet

wee

n s

hip

s,an

d (

2) t

o p

reve

nt

ship

sfr

om

losi

ng

th

eir

bea

rin

gs

and

get

tin

g lo

st a

t se

a.•

Wh

at d

oes

cali

brat

edm

ean

? S

amp

le a

nsw

er:

mar

ked

pre

cise

ly t

op

erm

it a

ccu

rate

mea

sure

men

ts t

o b

e m

ade

Rea

din

g t

he

Less

on

1.R

efer

to

the

figu

re.W

rite

a r

atio

usi

ng

the

side

len

gth

s in

th

e

figu

re t

o re

pres

ent

each

of

the

foll

owin

g tr

igon

omet

ric

rati

os.

A.

sin

N� MM

NP �B

.cos

N� MN

P N�

C.

tan

N�M N

PP �D

.tan

M� MN

P P�

E.

sin

M� MN

P N�F.

cos

M� MM

NP �

2.A

ssu

me

that

you

en

ter

each

of

the

expr

essi

ons

in t

he

list

on

th

e le

ft i

nto

you

r ca

lcu

lato

r.M

atch

eac

h o

f th

ese

expr

essi

ons

wit

h a

des

crip

tion

fro

m t

he

list

on

th

e ri

ght

to t

ell

wh

atyo

u a

re f

indi

ng

wh

en y

ou e

nte

r th

is e

xpre

ssio

n.

P

MN

a.si

n 2

0v

b.

cos

20ii

c.si

n�

10.

8vi

d.

tan

�1

0.8

iiie.

tan

20

ivf.

cos�

10.

8i

i.th

e de

gree

mea

sure

of

an a

cute

an

gle

wh

ose

cosi

ne

is 0

.8

ii.

the

rati

o of

th

e le

ngt

h o

f th

e le

g ad

jace

nt

to t

he

20°

angl

e to

th

ele

ngt

h o

f h

ypot

enu

se i

n a

20°

-70°

-90°

tria

ngl

e

iii.

the

degr

ee m

easu

re o

f an

acu

te a

ngl

e in

a r

igh

t tr

ian

gle

for

wh

ich

th

e ra

tio

of t

he

len

gth

of

the

oppo

site

leg

to

the

len

gth

of

the

adja

cen

t le

g is

0.8

iv.t

he r

atio

of

the

leng

th o

f th

e le

g op

posi

te t

he 2

0°an

gle

to t

hele

ngth

of

the

leg

adja

cent

to

it i

n a

20°-

70°-

90°

tria

ngle

v.th

e ra

tio

of t

he

len

gth

of

the

leg

oppo

site

th

e 20

°an

gle

to t

he

len

gth

of

hyp

oten

use

in

a 2

0°-7

0°-9

0°tr

ian

gle

vi.t

he

degr

ee m

easu

re o

f an

acu

te a

ngl

e in

a r

igh

t tr

ian

gle

for

wh

ich

th

e ra

tio

of t

he

len

gth

of

the

oppo

site

leg

to

the

len

gth

of

the

hyp

oten

use

is

0.8

Hel

pin

g Y

ou

Rem

emb

er

3.H

ow c

an t

he

coin

cos

ine

hel

p yo

u t

o re

mem

ber

the

rela

tion

ship

bet

wee

n t

he

sin

es a

nd

cosi

nes

of

the

two

acu

te a

ngl

es o

f a

righ

t tr

ian

gle?

Sam

ple

an

swer

:Th

e co

in c

osi

ne

com

es f

rom

co

mp

lem

ent,

as in

com

ple

men

tary

ang

les.

Th

e co

sin

e o

f an

acu

te a

ng

le is

eq

ual

to

th

e si

ne

of

its

com

ple

men

t.

©G

lenc

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ill37

4G

lenc

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eom

etry

Sin

e an

d C

osi

ne

of

An

gle

sT

he

foll

owin

g di

agra

m c

an b

e u

sed

to o

btai

n a

ppro

xim

ate

valu

es f

or t

he

sin

ean

d co

sin

e of

an

gles

fro

m 0

°to

90°

.Th

e ra

diu

s of

th

e ci

rcle

is

1.S

o,th

e si

ne

and

cosi

ne

valu

es c

an b

e re

ad d

irec

tly

from

th

e ve

rtic

al a

nd

hor

izon

tal

axes

.

Fin

d a

pp

roxi

mat

e va

lues

for

sin

40°

and

cos

40�

.Con

sid

er t

he

tria

ngl

e fo

rmed

by

the

segm

ent

mar

ked

40°

,as

illu

stra

ted

by

the

shad

ed

tria

ngl

e at

rig

ht.

sin

40°

��a c�

��0.

164 �or

0.6

4co

s 40

°�

�b c��

�0.177 �

or 0

.77

1.U

se t

he

diag

ram

abo

ve t

o co

mpl

ete

the

char

t of

val

ues

.

2.C

ompa

re t

he

sin

e an

d co

sin

e of

tw

o co

mpl

emen

tary

an

gles

(an

gles

wh

ose

sum

is

90°)

.Wh

at d

o yo

u n

otic

e?

Th

e si

ne

of

an a

ng

le is

eq

ual

to

th

e co

sin

e o

f th

e co

mp

lem

ent

of

the

ang

le.

00.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.91

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

90°

10°

20°

30°

40°

50°

60°

70°

80°

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4 x

°0°

10°

20°

30°

40°

50°

60°

70°

80°

90°

sin

00.

170.

340.

50.

640.

770.

870.

940.

981

cos

10.

980.

940.

870.

770.

640.

50.

340.

170

1 0

40°

0.64

c �

1 u

nit

x°b

� c

os x

°0.

771

a �

sin

Exam

ple

Exam

ple

Answers (Lesson 7-4)

Page 10: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill 372 Glencoe Geometry

Use �LMN to find sin L, cos L, tan L, sin M, cos M, and tan M.Express each ratio as a fraction and as a decimal to the nearest hundredth.

1. � � 15, m � 36, n� 39 2. � � 12, m � 12�3�, n � 24

Use a calculator to find each value. Round to the nearest ten-thousandth.

3. sin 92.4 4. tan 27.5 5. cos 64.8

Use the figure to find each trigonometric ratio. Express answers as a fraction and as a decimal rounded to the nearest ten-thousandth.

6. cos A 7. tan B 8. sin A

Find the measure of each acute angle to the nearest tenth of a degree.

9. sin B � 0.7823 10. tan A � 0.2356 11. cos R � 0.6401

Find x. Round to the nearest tenth.

12. 13. 14.

15. GEOGRAPHY Diego used a theodolite to map a region of land for his class in geomorphology. To determine the elevation of a vertical rockformation, he measured the distance from the base of the formation to his position and the angle between the ground and the line of sight to the top of the formation. The distance was 43 meters and the angle was 36 degrees. What is the height of the formation to the nearest meter?

36�

43 m

41�x

3229

x �9

23

x �

11

15

5��105

CA

B

ML

N

Practice Trigonometry

NAME ______________________________________________ DATE ____________ PERIOD _____

7-47-4

Page 11: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill A12 Glencoe Geometry

Skil

ls P

ract

ice

Trig

on

om

etry

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

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____

____

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ER

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____

_

7-4

7-4

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Lesson 7-4

Use

�R

ST

to f

ind

sin

R,c

os R

,tan

R,s

in S

,cos

S,a

nd

tan

S.

Exp

ress

eac

h r

atio

as

a fr

acti

on a

nd

as

a d

ecim

al t

o th

e n

eare

st h

un

dre

dth

.

1.r

�16

,s�

30,t

�34

2.r

�10

,s�

24,t

�26

sin

R�

�1 36 4��

0.47

;si

n R

��1 20 6�

�0.

38;

cos

R�

�3 30 4��

0.88

;co

s R

��2 24 6�

�0.

92;

tan

R�

�1 36 0��

0.53

;ta

n R

��1 20 4�

�0.

42;

sin

S�

�3 30 4��

0.88

;si

n S

��2 24 6�

�0.

92;

cos

S�

�1 36 4��

0.47

;co

s S

��1 20 6�

�0.

38;

tan

S�

�3 10 6��

1.88

tan

S�

�2 14 0��

2.4

Use

a c

alcu

lato

r to

fin

d e

ach

val

ue.

Rou

nd

to

the

nea

rest

ten

-th

ousa

nd

th.

3.si

n 5

0.08

724.

tan

23

0.42

455.

cos

610.

4848

6.si

n 7

5.8

0.96

947.

tan

17.

30.

3115

8.co

s 52

.90.

6032

Use

th

e fi

gure

to

fin

d e

ach

tri

gon

omet

ric

rati

o.E

xpre

ss

answ

ers

as a

fra

ctio

n a

nd

as

a d

ecim

al r

oun

ded

to

the

nea

rest

ten

-th

ousa

nd

th.

9.ta

n C

10.s

in A

11.c

os C

� 49 0��

0.22

50�4 40 1�

�0.

9756

�4 40 1��

0.97

56

Fin

d t

he

mea

sure

of

each

acu

te a

ngl

e to

th

e n

eare

st t

enth

of

a d

egre

e.

12.s

in B

�0.

2985

17.4

13.t

an A

�0.

4168

22.6

14.c

os R

�0.

8443

32.4

15.t

an C

�0.

3894

21.3

16.c

os B

�0.

7329

42.9

17.s

in A

�0.

1176

6.8

Fin

d x

.Rou

nd

to

the

nea

rest

ten

th.

18.

19.

20.

28.8

73.5

15.9

19

x

33�

UL

S

27

x�8

BAC

27

x�

13 BA

C

41

409

B

A

C

sR

S Trt

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2G

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eom

etry

Use

�L

MN

to f

ind

sin

L,c

os L

,tan

L,s

in M

,cos

M,a

nd

tan

M.

Exp

ress

eac

h r

atio

as

a fr

acti

on a

nd

as

a d

ecim

al t

o th

e n

eare

st h

un

dre

dth

.

1.�

�15

,m�

36,n

�39

2.�

�12

,m�

12�

3�,n

�24

sin

L�

�1 35 9��

0.38

;si

n L

��1 22 4�

�0.

50;

cos

L�

�3 36 9��

0.92

;co

s L

��

0.87

;

tan

L�

�1 35 6��

0.42

;ta

n L

��

0.58

;

sin

M�

�3 36 9��

0.92

;si

n M

��

0.87

;

cos

M�

�1 35 9��

0.38

;co

s M

��1 22 4�

�0.

50;

tan

M�

�3 16 5��

2.4

tan

M�

�1.

73

Use

a c

alcu

lato

r to

fin

d e

ach

val

ue.

Rou

nd

to

the

nea

rest

ten

-th

ousa

nd

th.

3.si

n 9

2.4

0.99

914.

tan

27.

50.

5206

5.co

s 64

.80.

4258

Use

th

e fi

gure

to

fin

d e

ach

tri

gon

omet

ric

rati

o.E

xpre

ss

answ

ers

as a

fra

ctio

n a

nd

as

a d

ecim

al r

oun

ded

to

the

nea

rest

ten

-th

ousa

nd

th.

6.co

s A

7.ta

n B

8.si

n A

�0.

9487

�3 1��

3.00

00�

0.31

62

Fin

d t

he

mea

sure

of

each

acu

te a

ngl

e to

th

e n

eare

st t

enth

of

a d

egre

e.

9.si

n B

�0.

7823

51.5

10.t

an A

�0.

2356

13.3

11.c

os R

�0.

6401

50.2

Fin

d x

.Rou

nd

to

the

nea

rest

ten

th.

12.

64.4

13.

18.1

14.

24.2

15.G

EOG

RA

PHY

Die

go u

sed

a th

eodo

lite

to

map

a r

egio

n o

f la

nd

for

his

cl

ass

in g

eom

orph

olog

y.T

o de

term

ine

the

elev

atio

n o

f a

vert

ical

roc

kfo

rmat

ion

,he

mea

sure

d th

e di

stan

ce f

rom

th

e ba

se o

f th

e fo

rmat

ion

to

his

pos

itio

n a

nd

the

angl

e be

twee

n t

he

grou

nd

and

the

lin

e of

sig

ht

to

the

top

of t

he

form

atio

n.T

he

dist

ance

was

43

met

ers

and

the

angl

e w

as

36 d

egre

es.W

hat

is

the

hei

ght

of t

he

form

atio

n t

o th

e n

eare

st m

eter

?31

m

36� 43

m

41�

x

3229

x�9

23

x�

11

�10�

�10

3 �10�

�10

15

5��10

5 CA

B

12�

3��

12

12�

3��

2412� 12

�3�

12�

3��

24

ML

N

Pra

ctic

e (

Ave

rag

e)

Trig

on

om

etry

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4

Answers (Lesson 7-4)

Page 12: Answers (Lesson 7-1) · PDF fileAnswers NAME ... Lesson 7-1 F ind the geometric mean between each pair of numbers. State exact answers and answers to the nearest tenth. 1. 2 and 8

© Glencoe/McGraw-Hill A13 Glencoe Geometry

An

swer

s

Readin

g t

o L

earn

Math

em

ati

csTr

igo

no

met

ry

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4

©G

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3G

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eom

etry

Lesson 7-4

Pre-

Act

ivit

yH

ow c

an s

urv

eyor

s d

eter

min

e an

gle

mea

sure

s?

Rea

d th

e in

trod

uct

ion

to

Les

son

7-4

at

the

top

of p

age

364

in y

our

text

book

.

•W

hy

is i

t im

port

ant

to d

eter

min

e th

e re

lati

ve p

osit

ion

s ac

cura

tely

in

nav

igat

ion

? (G

ive

two

poss

ible

rea

son

s.)

Sam

ple

an

swer

s:(1

) To

avo

id c

olli

sio

ns

bet

wee

n s

hip

s,an

d (

2) t

o p

reve

nt

ship

sfr

om

losi

ng

th

eir

bea

rin

gs

and

get

tin

g lo

st a

t se

a.•

Wh

at d

oes

cali

brat

edm

ean

? S

amp

le a

nsw

er:

mar

ked

pre

cise

ly t

op

erm

it a

ccu

rate

mea

sure

men

ts t

o b

e m

ade

Rea

din

g t

he

Less

on

1.R

efer

to

the

figu

re.W

rite

a r

atio

usi

ng

the

side

len

gth

s in

th

e

figu

re t

o re

pres

ent

each

of

the

foll

owin

g tr

igon

omet

ric

rati

os.

A.

sin

N� MM

NP �B

.cos

N� MN

P N�

C.

tan

N�M N

PP �D

.tan

M� MN

P P�

E.

sin

M� MN

P N�F.

cos

M� MM

NP �

2.A

ssu

me

that

you

en

ter

each

of

the

expr

essi

ons

in t

he

list

on

th

e le

ft i

nto

you

r ca

lcu

lato

r.M

atch

eac

h o

f th

ese

expr

essi

ons

wit

h a

des

crip

tion

fro

m t

he

list

on

th

e ri

ght

to t

ell

wh

atyo

u a

re f

indi

ng

wh

en y

ou e

nte

r th

is e

xpre

ssio

n.

P

MN

a.si

n 2

0v

b.

cos

20ii

c.si

n�

10.

8vi

d.

tan

�1

0.8

iiie.

tan

20

ivf.

cos�

10.

8i

i.th

e de

gree

mea

sure

of

an a

cute

an

gle

wh

ose

cosi

ne

is 0

.8

ii.

the

rati

o of

th

e le

ngt

h o

f th

e le

g ad

jace

nt

to t

he

20°

angl

e to

th

ele

ngt

h o

f h

ypot

enu

se i

n a

20°

-70°

-90°

tria

ngl

e

iii.

the

degr

ee m

easu

re o

f an

acu

te a

ngl

e in

a r

igh

t tr

ian

gle

for

wh

ich

th

e ra

tio

of t

he

len

gth

of

the

oppo

site

leg

to

the

len

gth

of

the

adja

cen

t le

g is

0.8

iv.t

he r

atio

of

the

leng

th o

f th

e le

g op

posi

te t

he 2

0°an

gle

to t

hele

ngth

of

the

leg

adja

cent

to

it i

n a

20°-

70°-

90°

tria

ngle

v.th

e ra

tio

of t

he

len

gth

of

the

leg

oppo

site

th

e 20

°an

gle

to t

he

len

gth

of

hyp

oten

use

in

a 2

0°-7

0°-9

0°tr

ian

gle

vi.t

he

degr

ee m

easu

re o

f an

acu

te a

ngl

e in

a r

igh

t tr

ian

gle

for

wh

ich

th

e ra

tio

of t

he

len

gth

of

the

oppo

site

leg

to

the

len

gth

of

the

hyp

oten

use

is

0.8

Hel

pin

g Y

ou

Rem

emb

er

3.H

ow c

an t

he

coin

cos

ine

hel

p yo

u t

o re

mem

ber

the

rela

tion

ship

bet

wee

n t

he

sin

es a

nd

cosi

nes

of

the

two

acu

te a

ngl

es o

f a

righ

t tr

ian

gle?

Sam

ple

an

swer

:Th

e co

in c

osi

ne

com

es f

rom

co

mp

lem

ent,

as in

com

ple

men

tary

ang

les.

Th

e co

sin

e o

f an

acu

te a

ng

le is

eq

ual

to

th

e si

ne

of

its

com

ple

men

t.

©G

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ill37

4G

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eom

etry

Sin

e an

d C

osi

ne

of

An

gle

sT

he

foll

owin

g di

agra

m c

an b

e u

sed

to o

btai

n a

ppro

xim

ate

valu

es f

or t

he

sin

ean

d co

sin

e of

an

gles

fro

m 0

°to

90°

.Th

e ra

diu

s of

th

e ci

rcle

is

1.S

o,th

e si

ne

and

cosi

ne

valu

es c

an b

e re

ad d

irec

tly

from

th

e ve

rtic

al a

nd

hor

izon

tal

axes

.

Fin

d a

pp

roxi

mat

e va

lues

for

sin

40°

and

cos

40�

.Con

sid

er t

he

tria

ngl

e fo

rmed

by

the

segm

ent

mar

ked

40°

,as

illu

stra

ted

by

the

shad

ed

tria

ngl

e at

rig

ht.

sin

40°

��a c�

��0.

164 �or

0.6

4co

s 40

°�

�b c��

�0.177 �

or 0

.77

1.U

se t

he

diag

ram

abo

ve t

o co

mpl

ete

the

char

t of

val

ues

.

2.C

ompa

re t

he

sin

e an

d co

sin

e of

tw

o co

mpl

emen

tary

an

gles

(an

gles

wh

ose

sum

is

90°)

.Wh

at d

o yo

u n

otic

e?

Th

e si

ne

of

an a

ng

le is

eq

ual

to

th

e co

sin

e o

f th

e co

mp

lem

ent

of

the

ang

le.

00.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.91

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

90°

10°

20°

30°

40°

50°

60°

70°

80°

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

7-4 x

°0°

10°

20°

30°

40°

50°

60°

70°

80°

90°

sin

00.

170.

340.

50.

640.

770.

870.

940.

981

cos

10.

980.

940.

870.

770.

640.

50.

340.

170

1 0

40°

0.64

c �

1 u

nit

x°b

� c

os x

°0.

771

a �

sin

Exam

ple

Exam

ple

Answers (Lesson 7-4)