Adding Integers

1
2-1
Adding Integers
Warm Up
Lesson Presentation
Pre-Algebra
2
Warm Up Graph each number on a number line. 1.
5 2. 7 3. 4 4. 0
Add. 5. 22 19 6. 17 18
35
41
3
Learn to add integers.
Vocabulary
integer opposite absolute value
4
Integers are sets of whole numbers, including 0,
and their opposites.
To add numbers with like signs

• add the absolute values of the
• terms
• 2. and use the same sign as the terms.

5
Find the sum. A. 6 2 B. -6 (-2) C. 5
2 D. -5 (-2)
1. Sum is 8
1. Sum is 8
2. Solution is 8
2. Solution is -8
1. Sum is 7
1. Sum is 7
2. Solution is -7
2. Solution is 7
6
To add numbers with unlike signs
1. subtract the smaller absolute value from the
larger absolute value 2. and use the sign of
the term with larger absolute value.
7
Find the sum. A. -6 2 B. 6 (-2) C. -5
2 D. 5 (-2)
1. Difference is 4
1. Difference is 4
2. Solution is -4
2. Solution is 4
1. Difference is 3
1. Difference is 3
2. Solution is 3
2. Solution is -3
8
Find the sum. A. -8 -2 B. 3 (-1) C. 7
4 D. -9 6
1. Sum is 10
1. Difference is 2
2. Solution is -10
2. Solution is 2
1. Sum is 11
1. Difference is 3
2. Solution is 11
2. Solution is -3
9
Evaluate c 4 for c 8.
c 4
(8) 4
8 4
4
10
Evaluate d 7 for d 3.
d 7
(3) 7
3 7
4
11
Katrina opened a new bank account. Find her
account balance after the first four transactions
listed below.
Deposits 200, 20 Withdrawals 166, 38
200 20 (166) (38)
220 (204)
Katrinas account balance after the first four
transactions is 16.
12
Insert Lesson Title Here
Lesson Quiz Part 1
Add. 1. 7 ( 7) 2. 15 (9) (2)
14
4
Evaluate each expression for the given value of
the variable. 3. 13 r for r 15 4. 2 b
(9) for b 6
2
13
13
Insert Lesson Title Here
Lesson Quiz Part 2
5. On Monday, a local dog shelter had six dogs.
By Friday they had found homes for three, but
took in two more. Then how many dogs were in the
shelter?
5 dogs
14
Homework

• Pg 62
• 1 43 odd