Answer;
-Calculate the lengths of the diagonals, and show that they are equal.
-Calculate the slopes of every side, and show that adjacent sides are perpendicular.
Explanation;
-A parallelogram is a quadrilateral with 2 pairs of opposite, equal and parallel sides. If the diagonals of a parallelogram are congruent, then it’s a rectangle and also if a parallelogram contains a right angle, then it’s a rectangle.
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