WEBVTT

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Here is the problem: 4(x plus 7) equals negative 3x minus 3.

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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 3x to both sides.

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Subtract 28 from both sides.

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Divide both sides by 7.

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So the answer is x equals negative 31 over 7 approximately negative 4.4285714.

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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 4.4285714: left side equals 10.285714, right side equals 10.285714, which checks out.