WEBVTT

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Here is the problem: x/(x plus 1) equals 1 over 2.

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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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Multiply both sides by x plus 1 to clear the fractions. This is only valid where x plus 1 not equal to 0, so any value that makes it zero is excluded at the end.

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Isolate x.

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Now look at the graph of the left side minus the right side.

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It crosses zero exactly at the solutions we found.

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So the answer is x equals 1.

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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 1: left side equals 0.5, right side equals 0.5, which checks out.