1. QUIZ! Clear your desks except for last nights homework and a piece of scratch paper.

2. Example 3: Writing Equations a. The length of a rectangle is 4 less than twice the width. The perimeter of the rectangle is 24. What are the dimensions fo the rectangle? b. During a recent season, Miguel Cabrera and Mike Jacobs of the Florida Marlins hit a combined total of 46 homeruns. Cabrera hit 6 more homeruns than Jacobs. How many did each player hit?

3. 1-4 Absolute Value Equations Objectives: To solve inequalities using absolute value and to solve problems by making lists.

4. Hyper vs. Hypo Hypothermia and hyperthermia are similar words but have opposite meanings. Hypothermia is defined as a lowered body temperature. Hyperthermia is an extremely high body temperature. Both are potentially dangerous conditions, and can occur when a person’s body temperature is more 8 degrees above or below the normal body temperature of 98.6. At what temperatures do these conditions begin to occur?

5. Absolute Value** Definition: For any real number a: if a > 0 then |a| = a if a < 0 then |a| = -a The absolute value of a number is its distance to 0 on a number line.

6. Example 1: Evaluate an Expression with Absolute Value Evaluate 8.4 - |2n + 5| if n = -7.5 1A: |4x +3 | - 3½ if x = -2 1B: 1¼ - |2y + 1| if y = -¾

7. Example 2: Solve an Absolute Value Equation A standard adult tennis racket has a 100 square-inch head, plus or minus 20 square inches. Write and solve an absolute value equation to determine the least and greatest possible sizes for the head of an adult racket. 2A: 9 = | x + 12| 2B: 8 = | y + 5|

8. What is the absolute value of x – 15? Make a list of the possible cases: Case 1: If x > 15 then x – 15 > 0 so, x – 15 = x – 15 Case 2: If x is less than 15 then x – 15 < 0 so, x – 15 = -(x – 15) or 15 – x

9. Problem Solving Strategies** Problem Solving Strategies Draw a diagramSolve a similar problem Make a table or chartEliminate the possibilities Make a modelLook for a pattern Guess and checkAct it out Check for hidden assumptions Work backward Use a graphIdentify subgoals

10. List the possibilities Rosa forgot the personal identification number (PIN) for her ATM card. She remembered that her PIN is the rearranged digits of her house number, which is 1256. What PIN’s should she try in the ATM?

11. Evaluate Evaluate 3x – 6 + 3.2 if x = -2

12. Example* Solve the equation: x – 25 = 17, then check the solution. Think about what cases the absolute value can be 17…

13. Examlpe* Solve 2x + 7 + 5 = 0 Hint: Isolate the absolute value…

14. Example* Solve x – 2 = 2x – 10 List the cases … Check your answer …

15. Empty Set** Definition: The set having no members, symbolized by { } or O When an equation has no solution, the answer is said to be null or the empty set.