$\"\"$

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The equation is $\"\"$ .

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Solve the equation. \ \

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$\"\"$ (Original equation)

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$\"\"$ (Subtract $\"\"$ from each side)

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$\"\"$ (Divide each side by $\"\"$ ) \ \

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$\"\"$ (Cancel common terms) \ \

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Therefore, the formula for the $\"\"$ is $\"\"$ .

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$\"\"$ \ \

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The value of $\"\"$ . \ \