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1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13...

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PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4B PROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5B PROBLEM 5A ANGLES: CLASSIFICATION ADJACENT ANGLES ANGLE ADDITION POSTULATE SUPPLEMENTARY ANGLES LINEAR PAIR COMPLEMENTARY ANGLES VERTICAL ANGLES END SHOW PRESENTATION CREATED BY SIMON PEREZ. All rights re served
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Page 1: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

1

PROBLEM 1A

PROBLEM 2A

PROBLEM 1B

PROBLEM 2B

PROBLEM 3A

PROBLEM 4BPROBLEM 4A

PROBLEM 3B

STANDARD 13

ANGLES: INTRODUCTION

PROBLEM 5BPROBLEM 5A

ANGLES: CLASSIFICATION

ADJACENT ANGLES

ANGLE ADDITION POSTULATE

SUPPLEMENTARY ANGLES

LINEAR PAIR

COMPLEMENTARY ANGLES

VERTICAL ANGLES

END SHOWPRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 2: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

2

STANDARD 13:

Students prove relationships between angles in polygons using properties of complementary, supplementary, vertical and exterior angles.

ESTÁNDAR 13:

Los estudiantes prueban relaciones entre ángulos en polígonos usando propiedades de ángulos complementarios, suplementarios, verticales y ángulos exteriores.

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 3: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

3

STANDARD 13What is an angle?

How many ways may we call this angle?

ABC

CBA

B

1AB

C

1

AB

C

Common endpoint called: VERTEX

Non-collinear ray

Non-collinear Ray

INTERIOR

EXTERIOR

EXTER

IOR

AB

C

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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4

STANDARD 13 ANGLES

A

CF

B

D

E

12

34

How else may we call 2?

DFC or CFD

May be called F?

No, because point F has more than two rays departing from it.

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 5: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

5

STANDARD 13ANGLES CLASSIFICATION

ACUTE ANGLE: OBTUSE ANGLE:RIGHT ANGLE:

0° < ANGLE < 90° ANGLE = 90° 90° < ANGLE < 180°

STRAIGHT ANGLE:

ANGLE = 180°PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 6: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

6

STANDARD 13ANGLE RELATIONSHIPS

A

CF

B

D

E

12

34

2 and 3 are ADJACENT ANGLES because they have a COMMON RAY FC

ADJACENT ANGLES:

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 7: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

7

STANDARD 13ANGLE RELATIONSHIPS

A

CF

B

D

E

12

34

ADJACENT ANGLES:

Can you see other adjacent angles in the figure?

EFD DFCand ; common ray FD

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 8: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

8

STANDARD 13ANGLE RELATIONSHIPS

A

CF

B

D

E

12

34

ADJACENT ANGLES:

Can you see other adjacent angles in the figure?

CFB AFBand ; common ray FB

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 9: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

9

STANDARD 13ANGLE RELATIONSHIPS

A

CF

B

D

E

12

34

ADJACENT ANGLES:

Can you see other adjacent angles in the figure?

EFC AFCand ; common ray FC

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 10: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

10

STANDARD 13ANGLE RELATIONSHIPS

A

CF

B

D

E

12

34

ADJACENT ANGLES:

Are and adjacent?EFD BFA

NO, because they don’t have a common ray.PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 11: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

11

STANDARD 13ANGLE RELATIONSHIPS

A

CF

B

D

E

12

34

2 and 3 are ADJACENT ANGLES because they have a COMMON RAY FC

ADJACENT ANGLES:

Can you see other adjacent angles in the figure?

EFD DFCand

CFB BFAand

EFC AFCand

Are and adjacent?EFD BFA

NO, because they don’t have a common ray.

; common ray FD

; common ray FB

; common ray FC

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 12: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

12

STANDARD 13ANGLE RELATIONSHIPS: ANGLE ADDITION POSTULATE (Simplified)

LN

M

K

KNL m + LNMm = MNKm

Now may you find EFB?m

A

CF

B

D

E

EFB=m EFD m + DFCm + CFBm

It means: MEASURE of angle KNL

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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13

STANDARD 13SUPPLEMENTARY ANGLES

RS

T

75°

What kind of angles are these two angles?

F

HG

105°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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14

STANDARD 13SUPPLEMENTARY ANGLES

What kind of angles are these two angles?

75°

F

HG

105°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 15: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

15

STANDARD 13SUPPLEMENTARY ANGLES

What kind of angles are these two angles?

TSR m + FGHm = 180°

Two angles that added together are 180°, are called: SUPPLEMENTARY ANGLES.

75°105°

TSR FGHAngles and are SUPPLEMENTARY!

F

HG

105°

RS

T

75°

and each one is the SUPPLEMENT of the other.PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 16: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

16

STANDARD 13SUPPLEMENTARY ANGLES

64°

Find the measure of the supplement of the angle below:

180° – 64° = 116°

116°

Supplement:

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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17

STANDARD 13SUPPLEMENTARY ANGLES

Find the measure of the supplement of the angle below:

180° –145° = 35°145°

Supplement:

35°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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18

STANDARD 13SUPPLEMENTARY ANGLES

70°

Find the measure of the supplement of the angle below:

180° – 70° = 110°

110°

Supplement:

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 19: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

19

STANDARD 13

105° 75°

Let’s take a closer look at the angle formation we got before:

• They are supplementary: 105° + 75° = 180°

• They are adjacent: have a common ray.

• They are LINEAR PAIR: because they are all of the above!

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 20: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

20

32X + 10 8X +10 + = 180

40X +20 = 180-20 -20

40X = 16040 40

X= 4

This is a linear pair, so both angles are supplementary:

m RST = 32X + 10= 32( )+10

= 128 + 10

= 138°

m UST = 180-138

= 42°

4

R S U

T

32X + 10 8X + 10

STANDARD 13FIND: RST and UST

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 21: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

21

20X + 10 5X +20 + = 18025X +30 = 180

-30 -30

25X = 15025 25

X= 6

This is a linear pair, so both angles are supplementary:

m KLN = 20X + 10= 20( )+10

= 120 + 10

= 130°

m MLN = 180-130

= 50°

6

K L M

N

20X + 10 5X + 20

STANDARD 13FIND: KLN and MLN

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 22: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

22

STANDARD 13COMPLEMENTARY ANGLES

ML

K

60°A

B

C30°

What kind of angles are these two angles?

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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23

STANDARD 13COMPLEMENTARY ANGLES

A

B

C30°

What kind of angle are these two angles?

60°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 24: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

24

STANDARD 13COMPLEMENTARY ANGLES

What kind of angles are these two angles?

60°

30°KLM m + ABCm = 90°

Two angles that added together are 90°, are called: COMPLEMENTARY ANGLES.

KLM ABCAngles and are complementary!

ML

K

60°

A

B

C30°

and each one is the COMPLEMENT of the other.PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 25: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

25

STANDARD 13SUPPLEMENTARY ANGLES

Find the measure of the COMPLEMENT of the angle below:

90° – 35° = 55°

Complement

55°

35°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 26: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

26

STANDARD 13COMPLEMENTARY ANGLES

Find the measure of the COMPLEMENT of the angle below:

90° – 67° = 23°67° 23°

Complement

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 27: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

27

STANDARD 13COMPLEMENTARY ANGLES

Find the measure of the COMPLEMENT of the angle below:

90° – 39° = 51°

Complement

51°

39°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 28: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

28

9X + 10 20X-7 + = 90°29X +3 = 90

-3 -3

29X = 8729 29

Both angles are complementary:

m TRS = 9X+10= 9( ) + 10

= 27 + 10

m TRU = 90-37

3

X = 3

= 37°

= 53°

R

S

T

U

9X + 10

20X - 7

STANDARD 13FIND: TRS and TRU

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 29: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

29

7X + 12 13X-2+ = 90°

20X+10 = 90-10 -10

20X = 8020 20

Both angles are complementary:

m FGT = 7X+12= 7( ) + 12

= 28+ 12

m HGT = 90-40

4

X = 4

= 40°

= 50°

G

F

T

H

7X + 12

13X - 2

STANDARD 13FIND: FGT and HGT

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 30: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

30

STANDARD 13

q

s

Y

UV

X

Z

VERTICAL ANGLES

UZY VZX UZY=m VZXm

UZV YZX UZV=m YZXm

VERTICAL ANGLES are congruent, that is they have the same measure.

Observe they are straight lines

Means congruence

VERTICAL ANGLES are nonadjacent angles formed by two intersecting lines.

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 31: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

31

STANDARD 13VERTICAL ANGLES

M

KV

X

L

Are and vertical angles?KLM VLX

No, although they look to be formed by two intersecting lines, in reality LK and LX are two rays that don’t lie in the same line and therefore the angles aren’t vertical.

Note: two red lines in one angle means that such angle is different to the other with just one red line.

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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32

Both angles are vertical :

20 + 5X = 8X + 5

- 20 -20

5X = 8X -15

-8X -8X

-3X = -15-3 -3

X= 5

m ABC = 20 + 5X

= 20 + 5( )

m CBE = 180-45

5

= 45°

= 135°

m CBEm ABC and are linear pair

C

A

D

E

B20 + 5X 8X + 5

STANDARD 13FIND: ABC and CBE

= 20 + 25

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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33

Both angles are vertical :

10 + 4X = 6X + 4

- 10 -10

4X = 6X -6

-6X -6X

-2X = -6-2 -2

X= 3

m SKR = 10 + 4X

= 10 + 4( )

m TKS = 180-22

3

= 22°

= 158°

m TKSm SKR and are linear pair

R

S

T

U

K10 + 4X 6X + 4

STANDARD 13FIND: SKR and TKS

= 10 + 12

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 34: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

34

40°

STANDARD 13

m KJO + m NJO = 180°

m KJO + 40° = 180°- 40 - 40

m KJO = 140°

m MJN + m NJO = 90°

m MJN + 40° = 90°- 40 - 40

m MJN = 50°

m MJO = 90°

Two perpendicular lines form 4 right angles, so:

m NJO = m LJKIf by vertical angles:

m MJK = 90° + 40°

= 130°

140°

50°

then

130°

FIND:

K

LM

N

O

J

KJO, MJN, MJO MJKand

40°

By supplementary angles:

By complementary angles:

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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35

STANDARD 13

m KJO + m NJO = 180°

m KJO + 35° = 180°- 35 - 35

m KJO = 145°

m MJN + m NJO = 90°

m MJN + 35° = 90°- 35 - 35

m MJN = 55°

m MJO = 90°

Two perpendicular lines form 4 right angles, so:

m NJO = m LJKIf by vertical angles:

m MJK = 90° + 35°

= 125°

145°

55°

then

125°

FIND:

K

LM

N

O

J

KJO, MJN, MJO MJKand

35°

By supplementary angles:

By complementary angles:

35°

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

Page 36: 1 PROBLEM 1A PROBLEM 2A PROBLEM 1B PROBLEM 2B PROBLEM 3A PROBLEM 4BPROBLEM 4A PROBLEM 3B STANDARD 13 ANGLES: INTRODUCTION PROBLEM 5BPROBLEM 5A ANGLES:

36STANDARD 13

A

E

B

C

D

(12x + 10)°

(5x + 8)°

(3x + 2)°

Find andDEC, CEB, AEB, if rays ED and EA are opposite at point E.

DEC m AEBm++ CEBmDEA=m

DEA=m 180° by definition of a STRAIGHT ANGLE.

Now using all the above information and the figure:

(3x + 2) + (12x + 10) + (5x + 8) = 180°

3x + 12x + 5x + 2 + 10 + 8 = 180

20x + 20 = 180

-20 -20

20x = 16020 20

x = 8

Let’s find the measure of the angles:

m DEC = 3x + 2

= 3( ) + 28

= 24 + 2

= 26°

m CEB = 12x + 10

= 12( ) + 108

= 96 + 10

= 106°

m AEB = 5x + 8

= 5( ) + 88

= 40 + 8

= 48°

Verifying solution:

26° + 106° + 48° = 180°

180° = 180°

DEA,If rays ED and EA are opposite at point E then is a STRAIGHT ANGLE and the following holds true by Angle Addition Postulate:

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved

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37STANDARD 13

B

F

C

D

E

(13x + 12)°

(3x + 5)°

(4x + 3)°

Find andEFD, DFC, BFC, if rays FE and FB are opposite at point F.

EFD m BFCm++ DFCmEFB=m

EFB=m 180° by definition of a STRAIGHT ANGLE.

Now using all the above information and the figure:

(4x + 3) + (13x + 12) + (3x + 5) = 180°

4x + 13x + 3x + 3 + 12 + 5 = 180

20x + 20 = 180

-20 -20

20x = 16020 20

x = 8

Let’s find the measure of the angles:

m EFD = 4x + 3

= 4( ) + 38

= 32 + 3

= 35°

m DFC = 13x + 12

= 13( ) + 128

= 104 + 12

= 116°

m BFC = 3x + 5

= 3( ) + 58

= 24 + 5

= 29°Verifying solution:

35° + 116° + 29° = 180°

180° = 180°

EFB,If rays FE and FB are opposite at point F then is a STRAIGHT ANGLE and the following holds true by Angle Addition Postulate:

PRESENTATION CREATED BY SIMON PEREZ. All rights reserved


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