Download Alg 1B CC Sec 12.1 Notes inked

Ch.12 Data Analysis and Probability
Alg 1B CC Sec12.1 Organizing Data Using Matrices
Matrix – a rectangular arrangement of numbers in rows & columns
 Plural is matrices
Element – each number in a matrix
 Matrices are equal if they are the same size & the elements in
corresponding positions are equal.
Add and Subtract Matrices by combining corresponding elements.
Ex.1: Find the sum or difference.
 5 2.7   3 3.9 
   4

7

3
2

 

a. 
8
 2 11   1

 

b. 4 3.2  6.5 4

 

1.5 5   0
3 

 
Why can’t you add or subtract matrices that are not the same size?
Scalar Multiplication – multiply each element by a scalar (real-number factor)
Ex.2: Find the product.
 1 7.1 

 3 2.4 
a. 2 
9 0


b. 5 4

4


 2 10 


Ex.3: Use the weather chart below.
a. Which city has the greatest average number of clear days in a full year?
b. Which city has the greatest average number of cloudy days in a full year?
p713: 9-12, 14-17, 18, 20-22