Transcript 1 2 3 4 5 6 7 8 - Bibb County Schools

2-1
Integers
Pg.76
Essential Question
 When would you need to use negative
integers in the real world?
Definitions
 integers- the set of whole numbers
and their opposites (positive or
negative)
 opposite- two numbers that are an
equal distance from zero on a number
line
 absolute value- the distance of a
number from zero on a number line;
shown by l l
INTRODUCTION TO INTEGERS
 Integers are positive and negative numbers.
…, -6, -5, -4, -3, -2, -1, 0, +1, +2, +3, +4, +5,
+6, …
 Each negative number is paired with a positive
number the same distance from 0 on a number
line. These numbers are called opposites.
-3 -2 -1
0
1 2
3
Integers
Numbers to the right of
zero are more than zero.
Numbers to the left of zero
are less than zero.
The numbers –1, -2, -3
are called negative
integers. The number
negative 3 is written –3.
Zero is neither negative nor
positive.
The numbers 1, 2, 3 are
called positive integers. The
number positive 4 is written
+4 or 4.
Negative numbers are used to…
1.
2.
3.
The answers are on the next 3 slides 
Negative Numbers Are Used
to Measure Temperature
Negative Numbers Are Used to
Measure Under Sea Level
30
20
10
0
-10
-20
-30
-40
-50
Negative Numbers Are Used to
Show Debt
Let’s say your parents bought a car but
had to get a loan from the bank for $5,000.
When counting all their money they add
in -$5.000 to show they still owe the bank.
Hint
If you don’t see a
negative or positive sign
in front of a number it is
positive.
9 = +9
Opposite Example 1
•The opposite of a number is the same distance
from 0 on a number line as the original number, but
on the other side of 0.
•Zero is its own opposite.
–4 and 4 are opposites
–4
4
•
•
–5–4–3–2–1 0 1 2 3 4 5
Opposite Example 2
Graph the integer -7 and its opposite on a
number line.
7 units
7 units
–7–6–5–4–3–2–1 0 1 2 3 4 5 6 7
Opposite Examples 3&4
Graph the integer and its opposite on a number line.
-9–8 –7–6–5–4 –3–2 –1 0 1 2 3 4 5 6 7 8 9
–8 –7–6–5–4 –3–2 –1 0 1 2 3 4 5 6 7 8
Absolute Value Video Clip (1:30)
Write down 1 fact from the
clip about absolute value.

http://player.discoveryeducation.com/index.cfm?guidAssetId=EE3ED6D096E6-4FF7-8D82-3FCD782528EB&blnFromSearch=1&productcode=US
Reading Math
The symbol is read as “the absolute value of.”
For example -3 is the absolute value of -3.
Absolute Value Example 1
Use a number line to find each absolute value.
|8|
8 units
–8 –7–6–5–4 –3–2 –1 0 1 2 3 4 5 6 7 8
8 is 8 units from 0, so |8| = 8.
Absolute Value Example 2
Use a number line to find each absolute value.
|–12|
12 units
–12 –11 –10 –9 –8 –7 –6 –5 –4 –3
–2
–1 0 1
–12 is 12 units from 0, so |–12| = 12.
2
Absolute Value Examples 3 & 4
2
–8 –7–6–5–4 –3–2 –1 0 1 2 3 4 5 6 7 8
7
–8 –7–6–5–4 –3–2 –1 0 1 2 3 4 5 6 7 8
You can compare and order integers by
graphing them on a number line.
•Integers increase in value as you move
to the right along a number line.
•They decrease in value as you move to
the left.
Remember!
The symbol < means “is less than,” and the
symbol > means “is greater than.”
Comparing Example 1
Compare the integers. Use < or >.
-4 > -11
-15 -14 -13 -12 -11 -10 -9 -8 -7
-6
-5
-4 -3 -2 -1
-4 is farther to the right than -11, so -4 > -11.
Comparing Example 2
Use a number line to order the integers
from least to greatest.
–3, 6, –5, 2, 0, –8
–8 –7–6 –5–4 –3 –2 –1 0 1 2 3 4 5 6 7 8
The numbers in order from least to greatest
are –8, –5, –3, 0, 2, and 6.
Comparing Examples 3&4
›
-18 -17 -16 -15 -14 -13 -12 -11 -10 -9
‹
-8
-7 -6 -5 -4
Comparing Example 5
–8 –7–6–5–4 –3–2 –1 0 1 2 3 4 5 6 7 8
Work Session-Together
 Showing off Integer WS
 Meaning of Integer WS
Work Session-With your Partner
Comparing and Ordering Sort
Work Session- On your own
Number Line WS
Closing
 When would you use negative numbers in
the real world?
 Do the numbers increase or decrease as
you move to the left of zero?
 < means:
 > means:
Homework
 13.3 WS Comparing and Ordering
Integers
Role of Integers
Video Clip
 Write down 3 facts about integers
from the clip.
 1.
 2.
 3.
http://player.discoveryeducation.com/index.cfm?guidAssetId=E2DCB058-17F3-41C9A4C8-B08D1D2AACB8&blnFromSearch=1&productcode=US
Homework
Workbook
pg. 13
All problems
Work Session
Textbook
Pg. 78
16-38 even only
GRADED