Ch. 4-1 Organizing Data into Matrices

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.

Write the dimensions of each matrix. Organizing Data Into Matrices a. 7 – 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

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

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

Identify each matrix element. K = Organizing Data Into Matrices 3 –1 – –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 – –4 7 –5 b. K = k 32 is the element in the third row and second column. 3 –1 – –4 7 –5

(continued) K = Organizing Data Into Matrices 3 –1 – –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 – –4 7 –5 d. K = k 34 is the element in the third row and the fourth column. 3 –1 – –4 7 –5 4-1

Check understanding P. 165 #2 A - D

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

Check understanding P. 165 # 3 A and B

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 N = Import Exports Each column represents a different year. Each row represents imports and exports Imports Exports

(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 Imports Exports

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

Homework P. 166 # 1 – 25 eoo