Question

Quadrilateral ABCD is a rectangle. If the coordinates of A

are (4,7) and B are (-6, 2), then the slope of BC is:
A. -2. B.2. C. 1/2. D. 2/5

Answer 1

Answer: A) -2

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Step-by-step explanation:

Let's find the slope of line AB

m = (y2-y1)/(x2-x1)

m = (2-7)/(-6-4)

m = (-5)/(-10)

m = 1/2

The slope of line AB is 1/2

To get the slope of BC, we flip the fraction and the sign to get the perpendicular slope

1/2 becomes -2/1 or simply -2

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Slope of AB = 1/2

Slope of BC = -2

Notice how the two perpendicular slopes multiply to -1.

We know they are perpendicular because the four angles of any rectangle are always 90 degrees each.