WEBVTT

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Here is the problem: 4x minus 10 equals negative x plus 9.

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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 1x to both sides.

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Add 10 to both sides.

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Divide both sides by 5.

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So the answer is x equals 19 over 5 approximately 3.8.

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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 3.8: left side equals 5.2, right side equals 5.2, which checks out.