Unit 1 Day 1: The Real Number Line Essential Questions: What types of numbers can we plot on a number line? Where can we see number lines in the real world?

Vocabulary Number line: a line on which numbers are marked at intervals, used to represent simple numerical data. Origin: the “middle” of the number line at the point zero. Positive: numbers to the right of zero on the number line. Negative: number to the left of zero on the number line.

The Real Number Line -4 -3 -2 -1 0 1 2 3 4 negative numbers positive numbers Every real number has a place on the number line (even fractions and decimals!)

Example 1: Plot the points -3.2, ½, 0, 1.7 and 4 on the number line. -4 -3 -2 -1 0 1 2 3 4 1 2 3 4 -1 -2 -3 -4 -3.2 1/2 1.7 Example 2: Plot ¼ and -2.3 on a number line. Then, write two inequalities that compare the two numbers. -4 -3 -2 -1 0 1 2 3 4 -2.3 1/4 1 2 3 4 -1 -2 -3 -4 -2.3 < 1/4 or 1/4 > -2.3

Example 3: Plot the high temperatures from the table that shows the temperatures in Antarctica for one week. -48, -56, -56, -36, -51, -63, -68 -68 -51 -80˚ -60˚ -40˚ -20˚ 0˚ 20˚ 40˚ 60˚ 80˚ -63 -56 -48 -36 -40 -30 -20 -10 -50 -60 -70 -80

Application: Football 20 10 40 30 50 -10 -20 -30 -40 -50 30 A football field is like one giant number line. Gaining and losing yards moves you left and right on the number line, much like adding and subtracting.

Create Your Own! Make your own number line that demonstrates a real world application. Be creative! Once you have finished explain your number line to the person next to you.

Lets Play Some Integer Football! http://www.mathgoodies.com/games/integer_game/football.html

Summary Essential Questions: What types of numbers can we plot on a number line? Where can we see number lines in the real world? Use 1 minute to write 2 sentences answering the essential questions.