WEBVTT

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Here is the problem: 3x minus 10 equals negative 5x plus 15.

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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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Add 10 to both sides.

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Divide both sides by 8.

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So the answer is x equals 25 over 8 approximately 3.125.

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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 3.125: left side equals negative 0.625, right side equals negative 0.625, which checks out.