• What two numbers will give you a
product of 64 and a quotient of 4?
• 16 and 4
• 16 x 4 = 64
• 16 ÷ 4 = 4
Adding Integers
• We can use positive and negative
counters to model the addition of integers.
Positive Integer
Negative Integer
A positive integer paired with a negative integer form a
zero pair. The value of a zero pair is 0.
Add -2 + (-4)
= -6
Add 5 + 6
= 11
Add -3 + (-5)
= -8
Add -3 + -2 = -5
Do you notice a pattern or rule?
Comp book page 24
Adding Integers with like signs.
- add their absolute values,
keep the same sign as the
integers.
Examples:
-7 + (-3) = -10
5+4=9
Add -5 + 3
= -2
Remove all
the zero
pairs.
Add 4 + (-1) = 3
Remove all
the zero
pairs.
Add -6 + 5 = -1
Remove all
the zero
pairs.
Add 3 + (-7) = -4
Remove all
the zero
pairs.
Did you notice a pattern or rule?
Comp book page 24
Adding integers with unlike signs.
- When the signs are different,
subtract their absolute values,
keep the same sign as the integer
with the greater absolute value.
Examples:
8 + (-3) = 5
-8 + 3 = -5
Let’s try a few examples using the
rules for adding integers.
1)
2)
3)
4)
5)
6)
7)
-8 + 8 =
-9 + -11 =
13 + (-19) =
7+5=
-12 + 10 =
-22 + (-16) =
18 + (-5) =
0
-20
-6
12
-2
-38
13
Adding Integers with like signs.
- add their absolute values, keep the same
sign as the integers.
Adding integers with unlike signs.
- When the signs are different, subtract their
absolute values, keep the same sign as the
integer with the greater absolute value.