WEBVTT

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Here is the problem: 3(x minus 1) equals negative 2x plus 7.

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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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Add 2x to both sides.

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Add 3 to both sides.

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Divide both sides by 5.

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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 2.

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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 2: left side equals 3, right side equals 3, which checks out.