WEBVTT

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Here is the problem: 4x plus 8 equals negative 5x 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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Add 5x to both sides.

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Subtract 8 from both sides.

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Divide both sides by 9.

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So the answer is x equals negative 1 over 9 approximately negative 0.11111111.

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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 0.11111111: left side equals 7.5555556, right side equals 7.5555556, which checks out.