1. Algebra February 10, 2015 1

2. Systems of Three Variables We have already seen a system of two equations used to solve two variables. Now we are going to examine a system of three variables which requires three equations. 2

3. Systems of Three Equations Whenever you add another variable to the mix you MUST add another equation in order to solve it. 3

4. Systems of Three Equations: Process 4

5. 2. We then use this information and plug it into the other two equations in place of the variable. 3. We then use these two new equations and proceed to work through them the same as we would with other two variable, two equation systems. 2. We then use this information and plug it into the other two equations in place of the variable. 3. We then use these two new equations and proceed to work through them the same as we would with other two variable, two equation systems. 5

6. Example 1 6

7. Example 1-Continued 7

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11. Example 1- Continued 11

12. Example 2 12

13. Example 2- Continued 13

14. Example 2- Continued 14

15. Example 2- Continued 15

16. Example 2- Continued 16

17. Example 2- Continued 17

18. Example 2-Continued 18

19. Example 2- Continued 19

20. Homework Assignment 7-4 20