$\"\"$

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The expression is $\"\"$ .

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Rewrite the $\"\"$ is $\"\"$

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$\"\"$ (Substitute: $\"\"$ ) $\"\"$

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$\"\"$ (Distributive property: $\"\"$ )

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$ (Add: $\"\"$ ) $\"\"$

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The value of expression 21.75.

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