WEBVTT

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Here is the problem: negative 3(x plus 9) equals 6x minus 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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Simplify each side (distribute and combine like terms).

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Subtract 6x from both sides.

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Add 27 to both sides.

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Divide both sides by negative 9.

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So the answer is x equals negative 23 over 9 approximately negative 2.5555556.

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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 2.5555556: left side equals negative 19.333333, right side equals negative 19.333333, which checks out.