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3-1 Notes Add and Subtract Signed Numbers objecive: 1. add and subtract using a number line or rules. 2. use addition properties to find sums.
3-1 NotesAdd and Subtract Signed Numbers
objecive: 1. add and subtract using a number line or rules.2. use addition properties to find sums.
A number line can be used to show addition of two numbers.
Start at 0.
Move to the right to add a positive number.
Move to the left to add a negative.
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EXAMPLE 1: Use a number line to add.
A. 2 + 6B. 5 + (-3)C. -4 + (-1)D. -7 + 2E. 8 + (-8)
Two numbers the same distance from 0 but in opposite directions are known as OPPOSITES.
Absolute Value
To add numbers with the same signs,
To add numbers with different signs,
Example 2: ADD
A. -9 + (-3) B. 4 + (-16) C. -5 + 13 D. -12 + 0
Property of Addition
of Signed Numbers
Example 3: Subtract
A. -12 - 3 B. 6 - (-9) C. -14 - (-6) D. 5 - 15
Example 4:
The highest temperature recorded in Little Rock, Arkansas is 112 degrees Fahrenheit. The lowest is -5 degrees Fahrenheit. Find the difference between the high and low temperatures for Little Rock.
