1. Warm Up Graph: 1.y > 2x + 3 2.y < 1/3x – 2

2. M2 3.9 (M2) Graph & Solve Quadratic Inequalities Performance Exam: THURSDAY! Computer Lab: Friday Last Unit Test: Dec. 8 EOCT: Dec. 17

3. Vocabulary A quadratic inequality in two variables can be written in one of the following forms: y < ax² + bx + c y ≤ ax² + bx + c y > ax² + bx + c y ≥ ax² + bx + c

4. Vocabulary A quadratic inequality in one variable can be written in one of the following forms: ax² + bx + c < 0 ax² + bx + c ≤ 0 ax² + bx + c > 0 ax² + bx + c ≥ 0

5. Example 1: Graph the system y < -x² - x + 2 y ≥ x² - 2x – 2

6. Step 3: Identify the shaded region where the two graphs overlap. It is the graph of the system.

7. Example 2 Example 2 – Solve a quadratic inequality Solve x² - 5x ≤ - 4 a)Using a table Rewrite as x² - 5x + 4 ≤ 0 and make a table of values. x012345 x² - 5x + 4

8. The solution of the inequality is 1 ≤ x ≤ 4. b) Solve x² - 5x ≤ - 4 by graphing,

9. The solution of the inequality is 1 ≤ x ≤ 4.

10. c) Solve x² - 5x ≤ - 4 algebraically. First replace ≤ with =. x² - 5x = - 4 x² - 5x + 4 = 0 Factor. (x – 4)(x – 1) = 0 x = 4, 1 lessAND: 1 < x < 4

11. Classwork/Homework P. 98-99 #1-15odd, 28-33