WEBVTT

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Here is the problem: negative 2(x plus 3) equals negative 9x plus 7.

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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 9x to both sides.

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Add 6 to both sides.

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Divide both sides by 7.

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So the answer is x equals 13 over 7 approximately 1.8571429.

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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 1.8571429: left side equals negative 9.7142857, right side equals negative 9.7142857, which checks out.