WEBVTT

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Here is the problem: negative 2x minus 18 equals 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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Add 18 to both sides.

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Divide both sides by negative 2.

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So the answer is x equals negative 25 over 2 approximately negative 12.5.

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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 12.5: left side equals 7, right side equals 7, which checks out.