WEBVTT

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Here is the problem: (x plus 7)/5 plus (x minus 7)/5 equals negative 9.

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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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Divide both sides by 2 over 5 (multiply by its reciprocal).

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So the answer is x equals negative 45 over 2 approximately negative 22.5.

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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 22.5: left side equals negative 9, right side equals negative 9, which checks out.