3x3

This past week we learned how to do 3x3's and 4x4's. I will show examples of the 3x3 because the 4x4's take FOREVER and so much paper. However, they are pretty much the same concept so if you are able to do one, you can do the other. 3x3's are very simple once you are taught the correct way because it is all simple math. So, here we go:

Example 1: (I won't have the brackets around them because I don't know how to do that)

6 2 3
1 2 4
0 1 1

1. you want to pick the row with the smallest numbers and cross it out.
2. cross out the first column, so you are left with:

0 * 2 3
2 4
3. Now cross out the second column, and so on ( alternate the sigsn of subtraction and addition.)

0 * 2 3 + 1 * 6 3 - 1 * 6 2
2 4 1 4 1 2

4. Now just multiply your matrices.

8-5= 3 *0 = 0
24-3 = 21 * 1 = 21
12-2= 10 * 1 = 10

0 +21 -10= 11

11 is your answer!