WEBVTT

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Here is the problem: 1(x plus 7) equals negative 3x plus 6.

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A linear equation in x: isolate x using inverse operations.

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Start with the equation.

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Simplify each side (distribute and combine like terms).

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Add 3x to both sides.

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Subtract 7 from both sides.

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Divide both sides by 4.

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So the answer is x equals negative 1 over 4 approximately negative 0.25.

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Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves x alone.

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x equals negative 0.25: left side equals 6.75, right side equals 6.75, which checks out.