1. Ch. 4-1 Organizing Data into Matrices

2. Matrix: a rectangular array of numbers written within brackets The dimensions of a matrix is determined by the number of horizontal rows and vertical columns.

3. Write the dimensions of each matrix. Organizing Data Into Matrices a. 7 –4 12 9 The matrix has 2 rows and 2 columns and is therefore a 2  2 matrix. b. The matrix has 1 row and 3 columns and is therefore a 1  3 matrix. 0 6 15

4. Check understanding P. 164 # 1 A, B and C

5. Matrix Element Each number in a matrix is a matrix element. An element is identified by its position in the matrix.

6. Identify each matrix element. K = Organizing Data Into Matrices 3 –1 –8 5 1 8 4 9 8 –4 7 –5 a. k 12 b. k 32 c. k 23 d. k 34 Element k 12 is –1. Element k 32 is –4. a. K = k 12 is the element in the first row and second column. 3 –1 –8 5 1 8 4 9 8 –4 7 –5 b. K = k 32 is the element in the third row and second column. 3 –1 –8 5 1 8 4 9 8 –4 7 –5

7. (continued) K = Organizing Data Into Matrices 3 –1 –8 5 1 8 4 9 8 –4 7 –5 a. k 12 b. k 32 c. k 23 d. k 34 Element k 23 is 4.Element k 34 is –5. c. K = k 23 is the element in the second row and third column. 3 –1 –8 5 1 8 4 9 8 –4 7 –5 d. K = k 34 is the element in the third row and the fourth column. 3 –1 –8 5 1 8 4 9 8 –4 7 –5 4-1

8. Check understanding P. 165 #2 A - D

9. Three students kept track of the games they won and lost in a chess competition. They showed their results in a chart. Write a 2  3 matrix to show the data. Let each row represent the number of wins and losses and each column represent a student. Organizing Data Into Matrices = Win X = Loss Ed X X Jo X Lew X X X X EdJoLew Wins Losses

10. Check understanding P. 165 # 3 A and B

11. Refer to the table. a.Write a matrix N to represent the information. Organizing Data Into Matrices U.S. Passenger Car Imports And Exports (millions) Source: U.S. Department of Commerce. Use 2  3 matrix. 3.116 3.945 4.115 0.617 0.794 0.989 N = Import Exports 1980 1990 1995 Each column represents a different year. Each row represents imports and exports. 198019901995 Imports3.1163.9454.115 Exports0.6170.7940.989

12. (continued) b.Which element represents exports for 1995? Organizing Data Into Matrices U.S. Passenger Car Imports And Exports (millions) Source: U.S. Department of Commerce. Exports are in the second row. The year 1995 is in the third column. Element n 23 represents the number of exports for 1995. 198019901995 Imports3.1163.9454.115 Exports0.6170.7940.989

13. Check understanding 4 P. 166 # 4 A and B.

14. Homework P. 166 # 1 – 25 eoo