1. 11-3: Subtracting Integers
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2. 2 ways to help you subtract integers.
1. Use Color Counters
2. Mentally

3. SUBTRACTING INTEGERS (using color counters)
We often think of subtraction as a “take away” operation.
Which diagram could be used to compute
= ? +3 +3
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4. SUBTRACTING INTEGERS (using color counters)
This diagram shows adding 2 zero pairs.
Now we can take 5 yellow tiles away, we have 2 red tiles left.
We can’t take away 5 yellow tiles from this diagram. There is not enough tiles to take away!!
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5. SUBTRACTING INTEGERS (using color counters)
Use your red and yellow tiles to model each subtraction problem.
= ?
ANSWER
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6. -2 - -4 = +2 SUBTRACTING INTEGERS Now you can take away 4 red tiles.
2 yellow tiles are left, so the answer is…
This representation of -2 doesn’t have enough tiles to take away -4.
If you add 2 zero pairs(adding zero) you would have a total of 4 red tiles and the tiles still represent -2.
= +2
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7. SUBTRACTING INTEGERS (using color counters)
Work this problem.
= ?
ANSWER
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8. +3 - -5 = +8 SUBTRACTING INTEGERS
Add enough zero pairs so you can take away 5 red tiles.
Take away 5 red tiles, you have 8 yellow tiles left.
= +8
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9. SUBTRACTING INTEGERS (using color counters)
Work this problem.
= ?
ANSWER
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10. -3 - +2 = -5 SUBTRACTING INTEGERS
Add two zero pairs so you can take away 2 yellow tiles.
Take away 2 yellow tiles, you have 5 red tiles left.
= -5
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11. Subtracting Integers Mentally, then check using color counters.
When you subtract integers you…….. ADD the OPPOSITE !!!!
9 – (-2)
+3 – (-1)
-5 – (-8)
-7 - 6

12. Practice Time 
P 585 # 1-7