6th Grade Math Textbook, Fundamentals

Lesson 1-4 for exercise sets. &KDSWHU 

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You can also use tiles and a number line to model subtraction

of integers with unlike signs.

Subtract: 5 (2)

Method 1 Use Tiles

Rename any absolute value expression before you subtract.

|5|  3

 5  3 | 5 | 5

 5 (3)

 8

(^1) |12| |22 |
 12  22
 12 (22)
 34
|10| |6|^3
 10  6
 10 (6)
 16
(^2) | 8 10 |
| 8 (10)|
|18|
18
4
You cannot remove
two 1 tiles because
there are no 1 tiles.
Adding zero pairs does not
change the value.
Now remove two 1 tiles.
The result is 7 tiles.
Remember: zero pair
1 (1)  0
Method 2 Use a Number Line

• Start at 0, move right to 5.


• Move right to add 2.

So 5 (2)  7.

 2  1 01234567 8

5

2

Think

(2) 2, so subtracting 2 is the

same as adding 2.

You also can use opposites to subtract integers with like signs.

Subtract:  3  2

 3 (2)

 3 (2)

 5

So  3  2 5.

Both addends are negative.

The result is negative.

Add the opposite of the

number being subtracted.

Subtract: 10 (3)

10 (3)

10  3

13

So 10 (3) 13.

Both addends are positive.

The result is positive.

Add the opposite of the

number being subtracted.

Find the difference.

1. 5  8 2. 5 (8) 3. 6 |15| 4.|16 | (9) 5.|6 (4)|

6.Discuss and Write Explain whether subtracting two negative integers

always results in a negative integer. Give examples to support your explanation.