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Triangle diamonds and parallelogram
A parallelogram with perpendicular sides is called a rectangle.
No
no it does not
Yes, if the parallelogram is a rhombus or a square.
By definition, a parallelogram two separate pairs has parallel sides. The only type of parallelogram that has perpendicular sides is a rectangle. All others have non-perpendicular sides.
A parallelogram is a rhombus if and only if the diagonals are perpendicular
No. A parallelogram has two parallel sides.
A parallelogram doesn't necessarily have any perpendicular sides, but it can. If it has one single 90-degree angle, then it has four of them, and it's a rectangle or square. A parallelogram without perpendicular sides is a rhomboid or rhombus.
A rhombus
rhombus