WEBVTT
Kind: captions
Language: en

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With all of the rules and scenarios,

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remembering how to add and subtract

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negative numbers can be difficult.

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Here's a little trick to help you

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remember. Let's say we want to solve

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3 plus -7. First, imagine a

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number line with a bird sitting on our

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first number, 3. The operation plus or

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minus tells you which end of the number

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line to look at. Since we're adding, our

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little bird will look right toward the

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positive end. Our second number tells us

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how far to move and which direction to

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move. We'll move forward if it's positive

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and backwards if it's negative. Since our

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second number is a -7, our little

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bird is going to move backwards seven

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spaces. Since he landed at -4,

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that's our answer: 3 plus -7

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equals -4.

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Let's try another one. What about

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-2 minus -4? Our first

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number is -2, so that's where

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we'll start. Our operation is a minus, so

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our bird will look left towards the

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negative end. Our second number is a

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-4; therefore, our bird will move

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backwards 4 spaces. Our bird landed

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at +2, and that's our answer:

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-2 minus -4 equals 2.

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Let's recap. The first number is where

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you start. The operation tells you where

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to look:

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Plus, right, or minus, left. The second

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number tells you how far to move and in

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which direction: positive, forward, or

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negative, backwards. Where you land is

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your answer.

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That's it! You now know a trick for

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adding and subtracting negative numbers.