$\"\"$

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The geometric progression $\"\"$ .

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Solve for $\"\"$ .

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Consider $\"\"$ .

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Multiply each side by $\"\"$ .

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$\"\"$

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Cancel common terms.

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$\"\"$

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Apply distributive property $\"\"$ .

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$\"\"$ \ \

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Add S to each side.

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$\"\"$

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$\"\"$

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Subtract rL from each side.

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$\"\"$

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$\"\"$

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Common r terms.

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$\"\"$ \ \

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Divide each side by $\"\"$ .

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$\"\"$

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Cancel common terms.

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$\"\"$ .

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$\"\"$

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The value of $\"\"$ .