The Real Number Line A1

THE REAL NUMBER LINE Putting things in order

WARM UP Complete the following using < or >. 

1.) $4.00 ____ $1.00

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2.) 1.5 _____ 1.05

Write these 5 numbers from least to greatest: 

3.) 3.2, ½, 0, 1.7, 5

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4.) 1.6, 0.6, 1.06, 1.66, 0.7

WHAT DO THESE NUMBERS MEAN?

Which temperature is coldest?

HOW COULD WE EXPLAIN CHANGE WITH NUMBERS?

HORIZONTAL VS. VERTICAL 

Think of a number line as a thermometer lying down.

LABEL If this is a thermometer, where would the zero go?  Where are the positive numbers?  Where are the negative numbers? 

LABEL 

Using your answer from Warm Up #3, plot and label the points on the number line.

HOW FAR? 

Absolute value means the distance from zero.

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This is what absolute value looks like:

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How far is|500| from 0? The number 500 is 500 steps away from zero.

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How far is |-327| from 0? ____________

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Steps are __________ ______________

|x|

FINDING THE OPPOSITE 

Plot 3 and -3 on the number line.

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3 and -3 are _____________ because each is ___ steps away from ___.

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You can read the expression –a as “the opposite of a”.

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If a = -2 then -a =

FINDING THE OPPOSITE Find the opposite of the following: 

8 = ________ ________

-⅚=

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-3 = _______ ________

3.8 =

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-2.01 ________ ________

.37 =

WHAT DO WE KNOW ABOUT ABSOLUTE VALUE? 

If x is a positive number, then |x| = ________

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If x is zero, then |x| = ________

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If x is a negative number, will |x| be positive or negative?

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Absolute value is ___________ _______________!!!!!!!!

NOW WHAT? 

Solve:

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-|-8|= ________ ________

|0-6|=

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|5-2|= _______ ________

|2-5|=

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|x|= 7 ________ ________

|x|= -5

WRAP IT UP Decide whether the statement is true or false:

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The opposite of a number is always negative.

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The absolute value of a number is never negative.

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The expression -a is never positive.

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The expression -a is sometimes greater than a.

CLOSER Write 3 things you learned in this lesson. 

1.

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2.

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3.

HOMEWORK In golf the total score is given as the number of swings above or below par. Par is your expected score. Even par means your score is zero. The player with the lowest score wins. Use the table to answer the questions on the following page. Player

Score

Luciana Bemvenuti

+6

Liz Early

+15

Michelle Estill

-9

Annika Sorenstam

+1

Jenny Lidback

-4

Joan Pitcock

-11

Nancy Scranton

+4

Tiger Woods

-19

HOMEWORK

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Who scored closest to even par? Who scored farthest from even par? How many players scored above even par? Who?

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How many players scored below even par? Who?

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Who won the tournament?

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Are there any scores that are opposites listed in the table? If so, which players had those scores?

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