$\"\"$

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The equation is $\"\"$ .

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$\"\"$ (Substitute r = 4)

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

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

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$\"\"$ (Absolute value of $\"\"$ )

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Compare the values the equation is true. $\"\"$

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The given number is a solution to the equation.

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