WEBVTT
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William is playing a board game.
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From start, he moves 10 spaces forward.
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In his next turn, he moves six spaces back.
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How many spaces away from start is he now?
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If William begins on start and he moves 10 spaces forward.
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On his next turn, he moves six spaces back.
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We want to know how many spaces is he away from start.
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For this unknown value, we can use the variable π₯.
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What kind of equation can we write to model the situation?
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We can write it a few different ways.
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First, William went forward 10 spaces.
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So, we can start with positive 10.
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And then, he went back six spaces.
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We can represent that mathematically with negative six.
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If you take positive 10 and subtract six, youβll get π₯, the number of spaces away he is from the start.
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10 minus six equals four.
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And that means our π₯-value is four.
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Currently, the way itβs written: it says four equals π₯.
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But itβs fine to rearrange it in a more common way: π₯ equals four.
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10 minus six equals π₯ is only one way to model this situation with an equation.
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We could say that π₯ β the number of spaces away from start William is β plus the six places backwards he walked must be equal to the 10 total forward spaces.
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If π₯ plus six equals 10, then we can solve the problem by subtracting six from both sides of the equation.
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π₯ plus six minus six equals π₯ plus zero, which is π₯, and 10 minus six equals four.
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Both methods show us that William is four places away from start.