WEBVTT

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Here is the problem: negative x plus 1 equals 3x 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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Subtract 3x from both sides.

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Subtract 1 from both sides.

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Divide both sides by negative 4.

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So the answer is x equals negative 3 over 2 approximately negative 1.5.

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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 1.5: left side equals 2.5, right side equals 2.5, which checks out.