WEBVTT

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Here is the problem: 0.2(x minus 5) equals 0.5x plus 1.

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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 1 over 2x from both sides.

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Add 1 to both sides.

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Divide both sides by negative 3 over 10 (multiply by its reciprocal).

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So the answer is x equals negative 20 over 3 approximately negative 6.6666667.

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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 6.6666667: left side equals negative 2.3333333, right side equals negative 2.3333333, which checks out.