\"\"\"\"

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The equation is \"\"

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According to addition property of equality: if \"\", then \"\".

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\"\"   (Add 3x to each side)

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\"\"   (Commutative property: a + b = b + a)

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\"\"                 (Additive inverse property: \"\")

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\"\"                   (Additive identity property: \"\") \ \

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

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 \"\"

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  \"\"           (Subtract 12 from each side)

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\"\"                     (Additive inverse property: \"\")

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\"\"                           (Additive identity property: \"\") \ \

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  \"\"                                (Subtract: \"\")

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 \"\"

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  \"\"                             (Divide each side by 8)

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  \"\"                                 (Cancel common terms)

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

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 \"\"

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Check:

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

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  \"\"

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

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

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  \"\"                                          (Subtract:  \"\"  )

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 Compare the values, the equation is true.

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 \"\"

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The value of \"\".

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