From a Parallelogram to a Rectangle: Identifying and defining elements

Is the parallelogram below a rectangle?

The parallelogram in the drawing cannot be a rectangle because in a rectangle all angles are right angles, meaning they are equal to 90 degrees.

Angle A is greater than 90 degrees.

No

Is the parallelogram below a rectangle?

Let's calculate angle B:

$64+26=90$

The parallelogram in the drawing is indeed a rectangle since a parallelogram with at least one right angle is a rectangle.

Yes

Is the parallelogram below a rectangle?

Let's calculate angle A:

$92+33=125$

The parallelogram in the diagram is not a rectangle since angle A is greater than 90 degrees, and in a rectangle all angles are right angles.

No

The quadrilateral ABCD is a parallelogram.

$∢B=90°$

Is it a rectangle?

Yes.

Is this parallelogram a rectangle

No

Is this parallelogram a rectangle?

Yes

The quadrilateral ABCD is a parallelogram.

AD = CB

Is the parallelogram a rectangle?

_{^{Yes, a parallelogram with equal diagonals is a rectangle.}}

Perhaps all parallelogram is also a rectangle?

_{^{No, a rectangle necessarily has angles of 90°.}}

Given the following parallelogram:

Is it a rectangle?

No

Side DA is equal to side DE.

Is the parallelogram a rectangle?

Yes.