Aim: How do number lines help us to understand absolute value? September 24, 2009 Math 201 Objective: Students will understand absolute value of a number as the distance between a number and zero on a number line. Aim: How do number lines help us to understand absolute value? NYS Mathematics Standards: 6.N.13 Prior Knowledge: Identify each number as positive or negative: -4______ 5______ -17______ 11______ -8______ 13______

Mini-lesson: The absolute value of a number is the distance between the number and zero on a number line Ex. |-2| = 2 and |2| = 2 A number and its opposite always have the same absolute value because they are both equal distance from 0 on a number line. A number and its opposite are sometimes called a zero pair because together they cancel each other out (equal zero).

Guided Practice: Evaluate the expression |-4| On a number line, plot points 0 and -4. Count the units between the points. The distance between the points is 4 units, so |-4| = 4

Independent Practice: Group Activity: Use red and yellow counting disks to model +3 and -3. Form zero pairs to find the sum. Each yellow counter represents +1. Each red counter represents -1. Place 3 yellow disks and 3 red disks on your desk. Make 3 zero pairs using the yellow and red counting disks. Each pair of red and yellow disks equals zero and cancels each other. There are 0 remainig disks, so the sum is 0. Independent Practice: Complete exercises 19, 22, 23, 27 and 30.

Homework: 7 - 4 “Homework Practice” worksheet Assessment: Write each integer’s absolute value and the number needed to create its zero pair: -17, 3, -24, -59, 82 Homework: 7 - 4 “Homework Practice” worksheet