$\"\"$

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The equation is $\"\"$ . \ \ Case:1 a = b.

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$\"\"$

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Add 2m to each side.

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$\"\"$

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$\"\"$

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Subtract 15 from each side.

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$\"\"$

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$\"\"$

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Divide each side by 3.

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$\"\"$

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$\"\"$

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

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Case:2 a = $\"\"$ b.

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$\"\"$

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$\"\"$

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Add m to each side.

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$\"\"$

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$\"\"$

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Subtract 3 from each side.

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$\"\"$

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$\"\"$

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Multiply each side by negative one. \ \

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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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Product of two different sings is negative. \ \

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$\"\"$

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Product of two same sings is positive.

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$\"\"$

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$\"\"$

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The absolute value of 11 is 11.

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$\"\"$

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The equality is true. $\"\"$

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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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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ (The absolute value of $\"\"$ )

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The equality is true. $\"\"$

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The solution set is $\"\"$ .

\