Recognize different “classic types of graphs”Recognize different “classic types of graphs”

Recognize how the manipulated variable (x) Recognize how the manipulated variable (x) causes a change in the responding variable (y)causes a change in the responding variable (y)

AIM: What are some characteristics of graphs?

Best fit graphBest fit graph

Inversely (indirectly) proportionalInversely (indirectly) proportional

Directly proportionalDirectly proportional

AIM: What are characteristics of of line graphs?

• DEFINITION:

•a LINE GRAPH is a diagram which shows how changing one variable

•(the manipulated variable) X,

•causes a second (or responding) variable Y to also change in response.

• EXAMPLE: Number of Frog Croaks

Air Temp # of Croaks per minute

22 12

23 14

24 15

25 16

26 17

31 21

32 26

Step One: Draw your axis:

Step Two: label your axis:

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

30

Step Three: Plot your Points

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

30

Step Four: Draw your Line

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

30

Step Four: Draw your Line

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

30

Step Four: Draw your Line

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

30

• Line Graphs: Allow you to estimate trends: “As temperature increases what is happening to the number of croaks?”

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

25

• Line Graphs: Allow you to estimate trends: “As temperature decreases what is happening to the number of croaks?”

AIR TEMPERATURE Degrees C

22 23 24 25 26 27 28 29 30 31 32

# Croaks per per m

inute

10

15

20

25

Three Types of Line Graphs

• Best Fit

• Direct

• Indirect

• Line Graphs “Best Fit Graphs”

Normally, best first graphs are only done when the directions explicitly indicate to construct a “best fit graph”

AIM

: Wh

at i s a line grap

h?

Line Graphs:

Inverse Proportional vs. Directly Proportional Graphs!

GRAPH THIS:

Hours of Study Grade

.5 50

1 75

1.5 85

2 90

3 100

Hours of Study vs. Grades

0

20

40

60

80

100

0.5 1 1.5 2 2.5 3

Hours of Study

Gra

de o

n Te

st

GRAPH THIS:

Hours of TV Grade

1 100

2 90

3 85

4 75

5 60

Hours of Study vs. Grades

0

20

40

60

80

100

1 2 3 4 5

Hours of TV

Gra

de o

n Te

st

Hours of TV vs. Grades on Test

What is the difference between these two graphs?

As X increases, Y increases

Slopes Upward

Directly Proportional

As X increases, Y decreases

Slopes Downward

Indirectly or Inversely Proportional

Hours of Study vs. Grades

0

20

40

60

80

100

0.5 1 1.5 2 2.5 3

Hours of Study

Grad

e on T

est

Hours of Study vs. Grades

0

20

40

60

80

100

1 2 3 4 5

Hours of TVGr

ade o

n Test

Hours of TV vs. Grade

Class ACTIVITY:

Creating Line Graphs page 67

AIM: What is a Line Graph?

Homework:

INTERNET QUESTIONS

AIM

: Wh

at is a line grap

h?