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?
