1. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
Use a number line to find each sum.
a. 2 + (–3)
Start at 0. Move 2 units right.
Then move 3 units left.
The sum is –1.
b. –2 + 3
Start at 0. Move 2 units left.
Then move 3 units right.
The sum is 1.
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2. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
Use a number line to find each sum.
a. –7 + (–2)
Start at 0. Move 7 units left.
Then move another 2 units left.
The sum is –9.
b. –11 + (–1)
Start at 0. Move 11 units left.
Then move another 1 unit left.
The sum is –12.
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3. Adding and Subtracting Integers
COURSE 3 LESSON 1-4
Simplify each expression.
a. –7 + (–17)
Both –7 and –17 are negative, so the sum is negative.
–7 + (–17) = –24
b. 8 + (–32)
Find the absolute value of each integer.
|–32| – |8| = 24
Subtract.
32 – 8 = 24
8 + (–32) = –24
|–32| > |8|, so the sum is negative.
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