Download Absolute Value/Integers

Absolute Value/Integers
Integers/Absolute Value
• Four friends are waiting in line at a deli. Lisa is
in front of Sam. Sam is behind Gary and in
front of Maria. Gary is first. In what order are
they waiting?
Integers/Absolute Value
• Integer = set of positive #’s, negative #’s, and
zero.
• Positive Integers = whole #’s greater than zero.
• Negative Integers = whole #’s less than zero.
• Opposite Numbers = two #’s that are the same
distance from zero but on opposite sides of zero
on a number line.
• Absolute Value = total distance from zero on a #
line.
Integers/Absolute Value
│3│ =
│- 8│ =
│25│ =
│- 1│ =
│77│ =
│-144│ =
│62│ =
│- 91│ =
│5│ =
│- 13│ =
Integers/Absolute Value
I will point to a number, if it is an integer you will
say yes and then state its opposite. If not, say
no.
- 25
78
1.45
¼
2
33
- 453
4.8
54
- 47
½
4.56
-789
15.8
4
47
¾
- 89
7.586 - 1127
Integers/Absolute Value
• Use a greater than, less than, or equal sign to
show the relation between the following integers:
+12
-23
-3
0
+4
+2
-24
+6
Integers/Absolute Value
• Order the following integers from least to
greatest:
+4, 0, -3, -5
-5, -10, -12, -8
0, +5, +8, +17
Quiz
• Look at your card, now go
around the room and find
your opposite #.
• Look at your number, now as
a class, form a number line
that shows the values from
least to greatest.
Adding Integers
•
•
•
•
Red and yellow chips
Number lines
Army men
Face cards…
Subtracting Integers
• Robert’s checkbook balance was $15.
He deposited $20, wrote a check for
$25, and deposited $12. What was
his balance after these transactions?
Subtracting Integers
1st Integer
2nd Integer
Answer
+
+
+
-
+
?
-
+
?
Subtintegers is the same as adding the
opposite.
Subtract the absolute
values (sign remains
positive)
Subtract the absolute
values (sign remains
negative)
Add the absolute values
(sign matches the
integer with the greater
absolute value.)
Add the absolute values
(sign matches the
integer with the greater
absolute value.)
Subtracting Integers
*** You can also use the other methods we talked about like:
+4 - +9 =
- 8 – (-3) =
+5 – (-7) =
- 9 – (+2) =
- Red and Yellow Counting Chips
-Number lines
-Army Men
- Hot and Cold Cubes
-Thermometers
-Money
- Gains and Losses
- Deposits and Withdrawals
Subtracting Integers
+4 - +9 =
+2 - +7 =
- 8 – (-3) =
- 3 – (-4) =
+5 – (-7) =
+5 – (-6) =
- 9 – (+2) =
- 8 – (+9) =
0 – (-6) =
0 – +1 =
Quiz
1) +5 - +7 =
2) +2 – (-8) =
3) +4 – (-3) =
4) - 9 – (+6) =
Multiplying/Dividing Integers
• James bought a painting for $144.
The cost was 3/5 the original price of
the painting. What was the original
price of the painting?
Multiplying/Dividing Integers
+2 x -3
This means to add 2 groups of -3 to
zero.
Multiplying/Dividing Integers
-2 x +3
This means to remove 2 groups of +3 from zero.
Start with 0. Use pairs of yellow and red counters
to show 0. Then remove 2 groups of 3 yellow
counters.
Multiplying/Dividing Integers
-12 ÷ +4
This means to remove 2 groups of +3 from zero.
Start with 0. Use pairs of yellow and red counters
to show 0. Then remove 2 groups of 3 yellow
counters.
Multiplying/Dividing Integers
-8 ÷ -2
This means to remove 2 groups of +3 from zero.
Start with 0. Use pairs of yellow and red counters
to show 0. Then remove 2 groups of 3 yellow
counters.
Multiplying/Dividing Integers
1st Integer
2nd Integer
Answer
+
+
-
+
+
+
+
-
1) Temporarily ignore the
signs and multiply or
divide like normal.
2) Look back at the original
signs to determine the
sign of the answer.
- If the signs match
the answer will be
positive.
- If the signs do not
match the answer will
be negative.
Quiz
1)-4 x -6
2)-7 x +10
3)+8 x -2
4)+5 x +3
5)-54 x 0
1)-36 ÷ -6
2)-15 ÷ +3
3)+54 ÷ -9
4)+12 ÷ +3
5)-54 ÷ 1