The length of a rectangle is shown below: On a coordinate grid from negative 6 to positive 6 on the x-axis and on the y-axis two points A and B are shown. The point A is on ordered pair 2, 1, and the point B is on ordered pair negative 1, 1. A straight line joins the points A and B. If the area of the rectangle to be drawn is 18 square units, where should points C and D be located, if they lie vertically below the line that connects B and A, to make this rectangle? (1 point) C(−1, −2), D(2, −2) C(−1, −8), D(2, −8) C(−1, −5), D(2, −5) C(−1, −6), D(2, −6)

The given points are 2 -(-1) = 3 units apart horizontally, so the remaining points will need to be 18/3 = 6 units below, vertically. Translating the given points down 6 gives ...

D = A -(0, 6) = (2, 1) -(0, 6) = (2, -5)

C = B -(0, 6) = (-1, 1) -(0, 6) = (-1, -5)

The two points required to make a rectangle with an area of 18 square units are ...

C(-1, -5), D(2, -5)

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The area of a rectangle is the product of length and width. If the area is 18 square units, and the width is 3 units, then the length must be 6 units. 3×6=18.