Arranging the given equation in slope-intercept form ( y = mx + b ):
<em>We know that the perpendicular line would have a slope (m) that is </em><em>negative reciprocal </em><em>of this (). Thus we can write the perpendicular line's equation as . </em>
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<em>Now putting x = 4 and y = -6 into the equation, we can solve for b:</em>
If they made this trade, it would make sense that Mark would also have to give Ella $200. This is because the difference in value is that amount in the favor of Ella. You can see that by subtracting the two values from each other.