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2-2 Adding Integers
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Find each absolute value.
2-2 Adding Integers
Learn to add integers.
2-2 Adding Integers
SAME
Positive
DIFFERENT
Negative
there is more of
2-2 Adding Integers
Adding Integers
Same Sign Sum
Sign Different Difference
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2-2 Adding Integers
Example A: Find the sum -2+(-3)
-2 + (-3)
• Check the signs, they
the same
are________________.
Add
Combine
• __________(______)
the
integers.
• The original signs were the
same, so the sum has the
same sign, which is
Negative
________________.
2-2 Adding Integers
Example B: Find the sum -10 + 4
-10 + 4
• Check the signs, they
are________________.
Different
Eliminate Subtract the integers.
• __________(_________)
• The original signs were different, so the
sum has the sign of the integer there is
more of.
-10 is
• Since the absolute value of ____
greater than the absolute value of
4
_____,
the answer will have the sign of
___________________.
Negative
2-2 Adding Integers
Example C: Find the sum -1 + 4
-1 + 4
• Check the signs, they
are________________.
Different
Eliminate Subtract the integers.
• __________(_________)
• The original signs were different, so the
sum has the sign of the integer there is
more of.
4 is
• Since the absolute value of ____
greater than the absolute value of
-1 the answer will have the sign of
_____,
___________________.
Positive
2-2 Adding Integers
Example D: A football team gains 8 yards on one play and then
loses 13 yards on the next. Write an expression using integer
addition to represent the situation. Simplify your expression to
find the team’s total yardage.
•Write the expression, a number sentence with no
“=” sign.
•Simplify.
•Check the signs, they are___________________
Different
Eliminate Subtract
•__________(_________)the
integers.
-13
•Since the absolute value of______is
greater than
8
the absolute value of_______,
the answer will
Negative
have the sign of_____________.
Label
•____________
your answer. This is required for
all word problems.
2-2 Adding Integers
Example E:
In his first three rounds of golf, Roger got 3 under par,
5 over par, and 3 under par. What is Roger’s
combined score after all three rounds?
-3 + 5 + -3
2 + -3
-1
2-2 Adding Integers
1) 9+3
12
2) -4+(-2)
-6
3) 7+(-9)
-2
5) 7+8
15
7) -25+10
-15
4) -3+6
3
6) -1+(-12)
-13
8) 31+(-20)
11
2-2 Adding Integers
Exit Pass
1. 2 + 5
4. -7 + 15
2. -6 + (-8)
5. -10 + (-2)
3. -18 + 12
2-2 Adding Integers
-5 + (-6) =
Extra Practice
7 + 33 =
-7 + 3 =
-23 + (-46) =
2 + (-8) =
42 + (-21) =
4 + (-12) =
-86 + 45 =
-13 + (-21) =
-68 + 97 =
2-2 Adding Integers
Adding Integers
1. Positive + Positive
Example: 8 + 5 = 13
Rule: Add the numbers together and give
the answer a positive symbol
2-2 Adding Integers
2. Negative + Negative
Example: -8 + -7 = -15
Rule: Add the numbers together and give
the answer a negative symbol
2-2 Adding Integers
3. Positive + Negative OR
Negative + Positive
Example: 5 + -2 = 3
Example: -6 + 4 = -2
Rule: Subtract the smaller number from
the larger number and give the answer
the sign of the number with the larger
absolute value
2-2 Adding Integers
Examples
Find each sum.
–4 + 8
The signs are different. Find the difference
of the absolute values.
–4 + 8
4
Think: 8 – 4 = 4.
Use the sign of the
integer with the
greater absolute
value.
2-2 Adding Integers
Find each sum.
–13 + (–24)
The signs are the same. Find the sum of the
absolute values.
–13 + (–24) Think: 13 + 24 = 37.
–37
Use the sign of the two integers.
2-2 Adding Integers
Find each sum.
23 + (–35)
The signs are different. Find the difference of
the absolute values.
23 + (–35)
–12
Think: 35 – 23 = 12.
Use the sign of the integer with the
greater absolute value.
2-2 Adding Integers
Find each sum.
–5 + 3
The signs are different. Find the difference of
the absolute values.
–5 + 3
–2
Think: 5 – 3 = 2.
Use the sign of the
integer with the
greater absolute
value.
2-2 Adding Integers
Lesson Quiz for Student Response Systems
1. Find the sum.
A. 22
B. 12
C. –12
D. –22
–5 + (–17)
2-2 Adding Integers
Lesson Quiz for Student Response Systems
2. Identify the sum.
–18 + 26 + (–8)
A. –36
B. 0
C. 36
D. 52
2-2 Adding Integers
Lesson Quiz for Student Response Systems
3. Identify the sum.
–26 + 8 + (–5)
A. –23
B. –13
C. 0
D. 23
2-2 Adding Integers
Lesson Quiz for Student Response Systems
4. The cost of a guitar is $456. Helen has
$178 with her. Use integer addition to
identify how much more money she needs
to buy the guitar.
A. $296
B. $278
C. $196
D. $116