given three distinct quadrilaterals, a square, a rectangle, and a rhombus, which quadrilaterals must have perpendicular diagonals

Question

anonymous · Answer

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Which ones are perpendicular?

anonymous · Answer

oh ok

anonymous · Answer

the second

anonymous · Answer

Nope.
Remember that perpendicular means that the angle between the two is 90 degrees.
Since the diagonals cross, the angles between all sides must the same for the the angle to be 90 degrees.

anonymous · Answer

In the case of the rectangle,
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Angles A and B are equal and angles C and D are equal, but none of the 4 angles are 90 degrees.