$\"\"$ $\"\"$ $\"\"$

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The inequality is $\"\"$ .

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Apply subtraction property of inequality: Subtract 9 from each side.

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$\"\"$

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$\"\"$ (Apply additive inverse property: $\"\"$ )

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$\"\"$ (Apply additive identity property: $\"\"$ $\"\"$ $\"\"$ (Subtract: $\"\"$ )

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$\"\"$ (Apply distributive property: $\"\"$ )

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

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Apply addition property of inequality: Add 21 to each side.

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$\"\"$

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$\"\"$ (Apply additive inverse property: $\"\"$ )

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$\"\"$ (Apply additive identity property: $\"\"$ )

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

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Apply division property of inequality: If $\"\"$ then $\"\"$ .

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$\"\"$ (Divide each side by 3)

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$\"\"$ (Cancel common terms)

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$\"\"$ (Divide: $\"\"$ )

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$\"\"$

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$\"\"$

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Check:

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To check, substitute a number 11 or less than or equal to 11, in $\"\"$ .

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

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$\"\"$ (Substract: $\"\"$ )

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

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

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The inequality is true. $\"\"$

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The inequality solution set is $\"\"$ .