$\"\"$

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The given expression $\"\"$ .

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$\"\"$ (Prime factorization of 28, 16)

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$\"\"$ (Cancel common terms)

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$\"\"$

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$\"\"$

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$\"\"$

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The excluded value is $\"\"$

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$\"\"$

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$\"\"$ (Zero product property) $\"\"$

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The excluded value $\"\"$