\"\"\"\"

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The equation is \"\".

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\"\"                                (Product of two different signs is negative)

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According to additon property of equality: Add 18 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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Check:

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To check the solution, substitute \"\" in original equation.

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\"\"                  (Substitute \"\")

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

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The equation is true.\"\"

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The value of \"\".