$\"\"$

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The vertices of triangle ABC are $\"\"$ .

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Let AB, BC, and CA are adjacent sides of the quadrilateral.

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The vertices of line BC are $\"\"$ .

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Substitute the values of $\"\"$ in the slope formula $\"\"$ .

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$\"\"$ .

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The slope of line BC is $\"\"$ .

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Because the slopes of perpendicular lines are negative reciprocals, the slope of perpendicular line through $\"\"$ is $\"\"$ . $\"\"$

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To find the y - intercept, substitute the values of $\"\"$ in the slope - intercept from of equation $\"\"$ and solve for b.

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$\"\"$

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$\"\"$

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Add 12 to each side.

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$\"\"$

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$\"\"$ .

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Substitute the values of $\"\"$ in the slope - intercept form of equation $\"\"$ . $\"\"$

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The equation of perpendicular line is $\"\"$ .