The document discusses the relationship between various data sets, including the number of passengers and bus fare, and the number of notebooks and prices, using ordered pairs to represent these relationships. It also highlights how these relationships can be graphically depicted as straight lines when the quantities are integers and change continuously. The relationships are quantitatively expressed in terms of baht and involve specific numerical data.

1. Graphs of Linear
Equations

2. The relationship between the number of passengers and the bus fare
Number of Passengers
Bus fare (baht)
0
0
1
7
2
14
3
21
4
28
Ordered pairs:
0,0 1,7 2,14 3,21 4,28
In writing ordered pairs representing relations between two sets of
data, we must clearly define which data set is represented by the
first or the second entry. The order of the entries in ordered pairs
cannot be changed without changing the meaning of the pairs.

3. The relationship between the number of passengers and the bus fare
Number of
Passengers
Bus fare (baht)
0 1
7
14
21
28
35
2 3 4 5

4. The relationship between the number of notebooks and the prices
Number of notebooks
Price (baht)
0
0
1
8
2
16
3
24
4
32
Ordered pairs:
0,0 1,8 2,16 3,24 4,32

5. Number of
notebooks
Price (baht)
0 1
8
16
24
32
40
2 3 4 5
The relationship between the number of notebooks and the prices

6. Daily Allowance of Rujarek
Day
Allowance (baht)
1
80
2
80
3
80
4
80
5
80
Ordered pairs:
1,80 2,80 3,80 4,80 5,80

7. Day
Allowance (baht)
0 1
40
80
2 3 4 5
The relationship between the number of notebooks and the prices

8. The right triangle ABC where ABC = 90° as shown in the figure below:
BAC (degrees)
ACB (degrees)
10 3
80
4
80
5
80
Ordered pairs:
10,80 20,70 30,60 40,50 50,40
A B
C
80
20
70
30
60
40
50
50
40
60
30
70
20
80
10
60,30
70,20 80,10

9. BAC (degrees)
(degrees)
0 10
10
20 30 40 50
The relationship between BAC and ACB
60 70 80 90
20
30
40
50
60
70
80
90

10. When the two sets of number are integers, the
graphs representing their relationship are
points aligned in straight lines
When the two assigned quantities change
continuously, the graphs showing their
relationship becomes a straight line

11. Number of
notebooks
Price (baht)
0 1
8
16
24
32
40
2 3 4 5
The relationship between the number of notebooks and the prices