2. October 22, 2008
Addition of Integers
Windows(R) operating system and Mac OS X
operating system software
Submitted by: Gerry-Lynn Borys
Red Deer Catholic Regional Division: St.Patrick's
Community School
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4. October 22, 2008
Example
=+1 = -2
This is the same as This is the same as saying
saying (+3) + (-2) = +1 (+2) + (-4) = -2
5. October 22, 2008
Zero principle
The zero principle states that when you add two
opposites, their sum is equal to zero.
(+1) + (-1) = 0
6. October 22, 2008
So, in our two examples
left with
left with -2
+1
=0 =0 =0 =0
7. October 22, 2008
Use the yellow (positive) tiles and red
(negative)tiles to add each pair of integers, then
write the addition sentence for each.
(+5) + (-4)
(+3) + (-7)
(-4) + (-3)
9. October 22, 2008
You can also use a number line to add integers.
+ sign means move forward or to the right of zero
- sign means move back or to the left of zero
(+3) + (-2) Start at +3 and move
back 2 spaces
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12. October 22, 2008
You can also add integers algebraically.
Simply ignore the addition sign and
do what the sign on the second
integer tells you to do.
Example (+4) + (-5)
Ignore the addition sign and this
question becomes
4 - 5 = -1