Prove that the points A (1, 7), B (4, 2), C (-1, -1) and D (-4, 4) are the vertices of a square.
Vertices of a square ABCD are: A (1, 7), B (4, 2), C (-1, -1) and D (-4, 4) Length of side AB =
Length of side AB =
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units
Length of side BC =
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units
Length of side CD =
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units
Length of side DA =
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units
Length of diagonal BD =
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Length of diagonal AC =
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units
Since opposite sides are equal and diagonal are equal. Therefore given vertices are the vertices of a square.
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