WEBVTT

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Here is the problem: (x minus 8)/5 plus (x plus 6)/4 equals 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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Add 1 over 10 to both sides.

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Divide both sides by 9 over 20 (multiply by its reciprocal).

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So the answer is x equals 22 over 9 approximately 2.4444444.

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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 2.4444444: left side equals 1, right side equals 1, which checks out.