1. Section 9.3 Systems of Linear Equations in Several Variables Objectives: Solving systems of linear equations using Gaussian elimination.

2. Ex 1. Solve the system using Gaussian elimination.

3. Ex 2. Solve using Gaussian elimination.

4. Class Work 1. Solve using Gaussian elimination.

5. Number of Solutions of a Linear System For a system of linear equations, exactly one of the following is true. 1.The system has exactly one solution. 2.The system has no solution. 3.The system has infinetly many solutions.

6. For a system to have exactly one solution we have three planes intersecting in one point.

7. For a system to have no solutions the planes have no point in common.

8. For a system to have infinitely many solutions the three planes intersect in a line.

9. Ex 3. Solve the following system using Gaussian elimination.

10. Ex 4 Solve the system using Gaussian elimination.

11. Class Work Solve using Gaussian elimination. 2. 3.

12. Class Work 4.

13. HW p658 17 - 25 odd, 33