1. Goal 4.03: Systems of Equations and Inequalities

2. We MUST know: Solving systems by graphing Solving systems by substitution Solving systems by elimination ** Applications

3. Most Important Thing to Remember with Systems of Equations: We need to find the point (x, y) where the two lines intersect! Most Important Thing to Remember with Systems of Inequalities: We need to find the intersection region where the two lines cross!

4. Solving Systems by Graphing Calculator: y = (Make sure PLOTS is off) (Put in equation) GRAPH 2nd Trace 5 - Intersect ENTER ENTER ENTER Y = 2x - 4 Y = x + 2

5. Solving Systems by Graphing 1. y = -4x + 12. y = ½ x + 4 y = 2x + 3 y = ½ x – 2

6. Solving Systems by Graphing with Inequalities Same on calculator! Except… Greater Less Example: Y x + 3

7. Which Quadrant is it in? Example: Y x + 3

8. Solving Systems by Substitution 1. y = -4x + 8 y = x + 7

9. Solving Systems by Substitution 2.2x + 3y = 4 y = 6x - 7

10. Solving Systems by Substitution Try… 1.y = 2x 4y + 2x = 14

11. Solving Systems by Elimination 10x - 12y = -64 6x + 12y = 96

12. Solving Systems by Elimination 2x + 5y = -22 10x + 3y = 22

13. When to use each method: Graphing: Substitution: Elimination: