Khan Academy on a Stick : Why Subtracting a Negative Equivalent to Adding a Positive

Khan Academy on a Stick

Adding and subtracting negative numbers

Negative Numbers Introduction
Example: Adding negative numbers
Example: Adding integers with different signs
Why Subtracting a Negative Equivalent to Adding a Positive
Negative number word problems 1
Adding decimals of different signs word problem
Adding/Subtracting negative numbers

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