Draw the following.

A parallelogram OKAY where OK = 5.5 cm and KA = 4.2 cm. Is it unique?

If we know both the diagonals and the angle between them, we can create a unique parallelogram. This angle is not provided.
Because the opposite sides of a parallelogram are equal to one another, even if we know the measurement of one side, we still need to know the size of the side that lies next to it. So, we must be aware of two metrics.
Let's assume we have drawn one side of the parallelogram and are ready to build it. We must know at least one angle in order to sketch another side.

In order to create a parallelogram, we therefore want at least 3 measurements in total.

The diagram will be,