WEBVTT

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Here is the problem: (x minus 1)/4 plus (x plus 2)/3 equals 4.

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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 5 over 12 from both sides.

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Divide both sides by 7 over 12 (multiply by its reciprocal).

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So the answer is x equals 43 over 7 approximately 6.1428571.

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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 6.1428571: left side equals 4, right side equals 4, which checks out.