6th Grade Math Textbook, Fundamentals

Lesson 1-3 for exercise sets. &KDSWHU 

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Find the sum.

1. 6 (4) 2. 17  7 3. 17 (7) 4. 92 (26)  3

5.Discuss and Write Explain how you can add integers with like signs and

with unlike signs. Give examples to support your explanation.

You can also use tiles and a number line

to add integers with unlike signs.

Add: 6 (4)

Add: 14 (34)

| 34 ||14| Subtract the absolute values.

34  14

20

So 14 (34) 20. |34| |14|,

so the sum is

negative.

1 Add:  3  8 (11)

8 (3)(11)

8  (14) Add.

 6

So  3  8 (11) 6.

Change the order to

add like signs.

|14| | 8 |, so the sum is

negative.

2

Key Concept

Add Integers with Unlike Signs

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• Use the sign of the addend with the
  greater absolute value for the sum.

You can also use absolute value to add integers with unlike signs.

Add:  9  13

|13||9|

13  9

4

So  9  13 4. |13 | |9 |, so the

sum is positive.

Method 1 Use Tiles

• Model each addend.

6  (4)

• Group and remove zero pairs.

/HW 

/HW 

Method 2 Use a Number Line

• Start at zero.


• Move right to add positive integers.


• Move left to add negative integers.

So 6 (4) 2.

 





 

Zero Pair

0  0  0  0  1  1  2