Download SKILL 37 Identify the Absolute Value of a Number

NS
SKILL 37
Identify the Absolute Value of a Number
TEACHING STRATEGY
1. Vocabulary Make sure students understand
the meaning of the term distance. Direct
students to the number line in Example 1. Ask
What is the distance between 22 and 0? [2]
Direct students to the number line in Example
2. Ask What is the distance between 25 and
2? [7]
2. Teach Review the information at the top of the
student page. Work though Example 1 with
students. Direct them to the number line. Ask
As you measure the distance from 3 to 0, how
many jumps do you make from unit to unit? [3]
What direction do you jump? [to the left] If you
measure the distance from 0 to 3, how many
jumps do you make from unit to unit? [3] What
direction do you jump? [to the right] Point out
that distance is always positive. Then work
though Example 2 with students. Write | n | 5
22 on the board. Ask Can that statement ever
betrue?[No.]Whynot?[Theabsolutevalueof
a nonzero number is always a positive value.]
3. Quick Check Look for this common error as
students solve the Quick Check exercises.
• Writingnegativeabsolutevaluesforpositive
numbers, indicating that the student
mistakenly believes the absolute value of a
number is the opposite of that number.
4. Next Steps Assign the practice exercises
to students who show understanding. For
students who need more support, provide
tutoring using the alternate teaching strategy.
Additional Teaching Resource
Online Transition Guide with Reteach
and Extra Practice worksheets from
previous grade levels
ALTERNATE INTERVENTION STRATEGY
Materials: scrappaper,TRT7(NumberLines)
Strategy: Practice identifying absolute values by
using a table that compares the distance from 0
of pairs of opposite numbers.
1. Draw the table below on the board. Have
students copy it on scrap paper.
Negative
Value
Distance
from 0
Positive
Value
21
1
22
2
23
3
24
4
25
5
2. Remind students that the absolute value of
a number is the distance on a number line
between that number and zero. Tell students
that they are going to complete the center
column by measuring the distance along a
number line between the given values and
zero.
3. Distribute blank number lines. Instruct
students to label their number lines in wholeunit intervals from 25 to 5.
4. For each of the values in the table, instruct
students to count the number of jumps
(the distance) between that value and zero.
Encourage students to make conjectures
about the relationship between | 2n | and | n |.
[They are equal.]
5. After students have completed the table,
write several numbers less than 25 and
several numbers greater than 5 on the board.
Ask students to identify the absolute value for
each number without using a number line.
Transition Guide Course 1
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NS
SKILL 37
Name
Date
Identify the Absolute Value of a Number
The absolute value of a number is the distance between that number and
zero on a number line.
The absolute value of any nonzero number is always positive.
Example 1 Absolute Value of
a Positive Number
Example 2
| 3 | is read as “the absolute value of 3.”
| 3 | means the distance between 3 and 0 on a
number line.
Absolute Value of
a Negative Number
| 23 | is read as “the absolute value of 23.”
| 23 | means the distance between 23 and 0 on a
number line.
3 units
3 units
22 21
0
1
2
3
4
5
25 24 23 22 21
0
1
2
23 is 3 units away from 0.
So, its absolute value is 3.
| 23 | 5 3
3 is 3 units away from 0.
So, its absolute value is 3.
| 3 | 5 3
Quick Check
Use the symbol | | to write the absolute values of the
following numbers.
1 2
2 26
3 27
4 1
5 25
7 8
8 9
9 6
11 12
12 28
10 29
13 11
94
14 215
6 24
15 0
© Marshall Cavendish International (Singapore) Private Limited.
Practice on Your Own
Use the symbol | | to write the absolute values of the
following numbers.
Math in Focus: Singapore Math
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Skill 37
Practice on Your Own
Quick Check
2. |26| 5 6
3. |27| 5 7
Practice on Your Own
4.
6.
8.
10.
12.
14.
|25| 5 5
|8| 5 8
| 6| 5 6
|12| 5 12
|11| 5 11
|0| 5 0
Quick Check
2. 30 ft
3. 25 m
Practice on Your Own
4. 16 cm
5. 22 ft
Quick Check
1. 20.93
Quick Check
1. 10 square inches or 10 in.2
2. 30 square yards or 30 yd2
3. 90 square millimeters or 90 mm2
Practice on Your Own
4. 66 square meters or 66 m2
5. 77 square feet or 77 ft2
6. 164.7 square yards or 164.7 yd2
Skill 40
Quick Check
1. 36 square feet or 36 ft2
2. 100 square meters or 100 m2
3. 144 square centimeters or 144 cm2
Practice on Your Own
625 square centimeters or 625 cm2
90.25 square inches or 90.25 in2
441 square millimeters or 441 mm2
213.16 square feet or 213.16 ft2
Skill 41
Quick Check
1. trapezoid; QT and RS
2. rhombus; BE and CD, BC and ED
3. parallelogram; WZ and XY , WX and ZY
3. 5.045
5. 15.6
8. 6.25
6. 52.32
9. 25
2. 8.2
3. 22.35
Skill 43
Quick Check
Practice on Your Own
4. 0.61
7. 4.57
5. 14.03
8. 0.62
6. 2.88
9. 12.48
2. 38.07
3. 2.595
Skill 44
Quick Check
1. 4.5
Practice on Your Own
4. 14.56
7. 0.084
5. 21.50
8. 32.46
6. 4.14
9. 27.93
2. 2.03
3. 0.17
Skill 45
Quick Check
1. 1.6
Practice on Your Own
4. 3.54
7. 2.5
5. 0.72
8. 2.49
6. 0.127
9. 0.088
2. 43
3. 22
Skill 46
Quick Check
1. 31
Practice on Your Own
4. 7
7. 31
5. 30
8. 18
6. 3
9. 66
2. 25.4
3. 18.9
Skill 47
Quick Check
1. 3.6
132
2. 47.317
Practice on Your Own
1. 28.1
6. 31 mm
Skill 39
4.
5.
6.
7.
Skill 42
4. 16.428
7. 19.018
Skill 38
1. 9 in.
5. trapezoid; SV and TU
6. parallelogram; DG and EF , DE and GF
5.
7.
9.
11.
13.
15.
|1| 5 1
|24| 5 4
|9| 5 9
|29| 5 9
|28| 5 8
|215| 5 15
4. rhombus; GJ and HI , GH and JI
© Marshall Cavendish International (Singapore) Private Limited.
1. |2| 5 2
Math in Focus®: Singapore Math
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