\"\"

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The equation is \"\".

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\"\"                            (Write the equation)

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Apply subtraction property of equality: if \"\".

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\"\"                (Subtract 9 from each side)

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\"\" (Rewrite as the summation)

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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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Check whether \"\" is a solution.

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\"\"                            (Write the equation)

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\"\"                       (Substitute \"\")

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

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\"\" is a solution.\"\"

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The solution is \"\".