WEBVTT

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Here is the problem: negative 3(x plus 7) equals 5x minus 8.

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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 5x from both sides.

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Add 21 to both sides.

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Divide both sides by negative 8.

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So the answer is x equals negative 13 over 8 approximately negative 1.625.

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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 1.625: left side equals negative 16.125, right side equals negative 16.125, which checks out.