Transcript Lesson 2-4B PowerPoint

(over Lesson 2-3)
Which choice shows the graph of the point W(4, –2)?
A.
B.
C.
D.
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2.
3.
4.
A
B
C
D
(over Lesson 2-3)
Which choice shows the graph of the point N(–3, 0)?
A.
B.
C.
D.
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2.
3.
4.
A
B
C
D
(over Lesson 2-3)
Which ordered pair is 5 units left and 3 units up from
the origin?
A. (–5, –3)
B. (5, –3)
C. (5, 3)
D. (–5, 3)
1.
2.
3.
4.
A
B
C
D
Main Idea and Vocabulary
Key Concept: Add Integers with Different Signs
Example 5:
Add Integers with Different Signs
Example 6:
Add Integers with Different Signs
Example 7:
Use the Additive Inverse Property
Example 8:
Use Integers to Solve a Problem
1.
• Add integers (2.2.8B) (M7.A.3.2.2).
D
• Opposites – numbers the same distance from
zero on a number line.
• additive inverse – sum of any number and its
additive inverse is 0 EX: 5 + (-5) = 0
Add Integers with Different Signs
Find 2 + (–7).
2 + (–7) = –5
Answer: –5
Subtract absolute values;
7 – 2 = 5. Since –7 has
the greater absolute value,
the sum is negative.
Find 5 + (–9).
A. –14
B. –4
C. 4
D. 14
1.
2.
3.
4.
A
B
C
D
Add Integers with Different Signs
Find –9 + 6.
–9 + 6 = –3
Answer: –3
Subtract absolute values;
9 – 6 = 3. Since –9 has the
greater absolute value, the
sum is negative.
Find 7 + (–3).
A. –10
B. –4
C. 4
D. 10
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2.
3.
4.
A
B
C
D
Use the Additive Inverse Property
Find 11 + (–4) + (–11).
11 + (–4) + (–11) = 11 + (–11) + (–4)
Answer: –4
Commutative
Property (+)
= 0 + (–4)
Additive Inverse
Property
= –4
Identity Property
of Addition
Find 5 + (–11) + (–5).
A. –21
B. –11
C. 6
D. 16
1.
2.
3.
4.
A
B
C
D
Use Integers to Solve a
Problem
OCEANOGRAPHY Oceanographers divide the ocean
into three light zones. The deeper the water, the less
light shines through. The middle zone is called the
Twilight Zone. The lowest part of this zone is 1,000
meters below the surface of the water. The top of this
zone lies 800 meters above the lowest zone. What is
the depth of the top of the zone? Write an addition
sentence to describe this situation. Then find the
sum and explain its meaning.
–1,000 + 800 = –200
Answer: The depth of the top of the middle zone is
200 meters below the surface of the water.
During an hour trading baseball cards with his
friends, Kyle increases the size of his collection by
12 cards and then loses nine cards. Write an addition
sentence to describe this situation. Then find its
sum.
A. –12 + (–9); –21
B. –12 + 9; –3
C. 12 + (–9); 3
D. 12 + 9; 21
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2.
3.
4.
A
B
C
D
REVIEW
1. -3 + 10
7
2. -15 + 8
-7
3. 7 + (-11)
-4
4. 14 + (-6)
8
5. -17 + 20 + (-3)
6. 15 + 9 + (-9)
0
15
End of the Lesson
Five-Minute Check (over Lesson 2–3)
Image Bank
Math Tools
Adding Integers
Comparing and Ordering Integers
Subtracting Positive and Negative Integers