WEBVTT

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Here is the problem: negative 8x plus 9 equals 3x plus 4.

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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 9 from both sides.

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Divide both sides by negative 11.

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So the answer is x equals 5 over 11 approximately 0.45454545.

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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 0.45454545: left side equals 5.3636364, right side equals 5.3636364, which checks out.