Warm-Up

1
Warm-Up
4 minutes
1) What are the dimensions of these matrices?
2) Solve for x and y.
2
4.1.2 Using Matrices to Represent Data

• Objectives
• Find sums and differences of matrices and the
  scalar product of a number and a matrix

3
Example 1
a) Find A B C.
A B C
5
13
-8
-10
11
-11
4
Example 2
Find -3B.
-3B
-15
-27
-3
6
33
-24
0
-3
45
5
Practice
1) Find 2A B 3C
6
Example 3
Represent the quadrilateral below as matrix R.
A
B
C
D
3
-4
-4
0
1
4
-3
-4
7
Example 4
Represent the quadrilateral below as matrix R.
Graph the polygon that is represented by the
matrix 3R.
A
B
C
D
3
-4
-4
0
1
4
-3
-4
A
B
C
D
9
-12
-12
0
3
12
-9
-12
8
Homework
p.221 19-23 odds,33,39,41-47 odds,59,61