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\"\"

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The expression is \"\".

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Addition property of equality:

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If xa = b, then xa + a = b + a, or x = b + a.

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\"\"                 (Add 5 to each side)

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

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

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\"\"

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Check:

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Check the solution by substituting \"\" in the original equation.

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\"\"

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\"\"                                   (Subtract: 12 - 5=7)

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\"\"

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The value of \"\"

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