INTEGERS & ABSOLUTE VALUE

1. INTEGERS & ABSOLUTE VALUE OBJECTIVE: I will model and solve problems involving absolute value

2. KEY VOCABULARY ABSOLUTE VALUE: the distance between a number and zero on a number line ABSOLUTE VALUE SIGNS: a pair of vertical rules used to indicate the absolute value OPPOSITES: two numbers that have the same absolute value but opposite signs.

3. Integers • Whole numbers and their opposites are integers such as 6 and -6. • Zero is also a whole number. 0 -6 6 Opposites

4. Horizontal Number Line • The zero point on a number line is the origin. • Positive integers are usually written without a “+” sign to the right of the origin. • Negative integers are written with a “–” sign to the left of the origin. Origin Positive numbers Negative number -5 -4 -3 -2 -1 0 1 2 3 4 5

5. Absolute Value • The absolute value is the distance from zero. • Bars are used to show absolute value. • l -2 l = 2 and l 2 l = 2 -2 0 2 2 from 0 2 from 0

6. Use a number line • To compare integers, plot the points on the number line, the number farther to the right is the larger number • Compare 1 and -3 ___________ *_______*_______________ -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 Since 1 is to the right of -3, 1 > -3 or Since -3 is to the left of 1, -3 < 1

7. Use a number line • To order integers from least to greatest, draw a number line and plot the points. • Order the integers -4, 7, 3, -2, and 1 from least to greatest. _________*____*_____*___*_________*_ -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 Order the integers by reading from left to right. -4, -2, 1, 3, 7

8. Example: Statistics • Below is a list of planets and their average temperatures. Order the temperatures from least to greatest. Planet Average Temperature (F) Earth 50 Mars (day) 72 Mars (night) -94 Mercury (day) 800 Mercury (night) -300 Venus 900 -300, -94, 50, 72, 800, 900

9. GUIDED PRACTICE • TEXTBOOK Page 106 • #1-10