To find the fourth vertex of the rectangle, we can start by drawing a diagram:
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| (2,4)
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--------.--------
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(?, ?) | (2,1)
|
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We know that opposite sides of a rectangle are parallel, so the fourth vertex must be located on the same horizontal line as the point (2, 1) and the same vertical line as the point (-4, 4). Therefore, the fourth vertex must be located at (-4, 1).
To find the dimensions of the rectangle, we can find the distance between the points (2, 1) and (2, 4) to get the length of one side, and the distance between the points (2, 1) and (-4, 1) to get the length of the other side.
Length = 4 - 1 = 3
Width = 2 - (-4) = 6
So the dimensions of the rectangle are 6 by 3.
To find the area of the rectangle, we can multiply the length and width together:
Area = Length x Width = 6 x 3 = 18 square units.