WEBVTT

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Here is the problem: 4x plus 20 equals 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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Subtract 20 from both sides.

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Divide both sides by 4.

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So the answer is x equals negative 9 over 2 approximately negative 4.5.

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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 negative 4.5: left side equals 2, right side equals 2, which checks out.