$\"\"$

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Substitute $\"\"$ in slope formula.

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$\"\"$

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$\"\"$

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Multiply each side by negative 14.

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$\"\"$

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$\"\"$

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$\"\"$

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Multiply each side by 4.

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$\"\"$

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$\"\"$

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$\"\"$

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

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Add 20 to each side.

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$\"\"$

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$\"\"$

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Divide each side by 4.

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$\"\"$

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$\"\"$

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$\"\"$

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The value of r is $\"\"$ .