1. Notes Over 10.5 Using Cramer’s Rule for a 2 x 2 System
Use Cramer’s Rule to solve the linear system.
Find the determinant of the coefficient Matrix
To find your x replace the x ’s in the coefficient Matrix with the constants
To find your y replace the y ’s in the coefficient Matrix with the constants

2. Notes Over 10.5 Using Cramer’s Rule for a 3 x 3 System
Use Cramer’s Rule to solve the linear system.
Find the determinant of the coefficient Matrix

3. Find the area of the triangle with the given vertices.
Notes Over 10.5
The Area of a Triangle
Find the area of the triangle with the given vertices.

4. Determine whether the points lie on the same line.
Notes Over 10.5
Test for Collinear Points
Determine whether the points lie on the same line.
Non-Collinear

5. Find an equation of the line through the two points.
Notes Over 10.5
Equation of a Line
Find an equation of the line through the two points.

6. Notes Over 10.5 Encoding a Message
Use the code in the book and the matrix to encode the message.
First, convert the letters to row matrices
Then multiply each uncoded row by matrix A

7. Notes Over 10.5 C O O L M A N Decoding a Message
Use the code in the book and the matrix to decode the message. C O O L M A N

8. Notes Over 10.5