square
Most quadrilaterals do not.
Most quadrilaterals will not have congruent diagonals: rectangles (incl squares) and isosceles trapezium are the exception.
The diagonals are perpendicular, but not necessarily congruent.
they are called parallelogram in which diagonals are equal
quadrilaterals are consecutive and opposite angles always congruent?
Rectangles
Not generally.
Most quadrilaterals do not.
Figures that do not always have congruent diagonals include trapezoids and general quadrilaterals. In a trapezoid, for instance, the diagonals can be of different lengths depending on the angles and side lengths. Similarly, most irregular quadrilaterals lack any specific properties that guarantee congruent diagonals. Only specific types of quadrilaterals, such as rectangles and squares, have congruent diagonals by definition.
A square and a rectangle have diagonals of the same lengths.
Most quadrilaterals will not have congruent diagonals: rectangles (incl squares) and isosceles trapezium are the exception.
rectangle and parallelogram
rectangle and parallelogram
there is nothing listed
Parallelograms or isosceles trapezium.
A square
No. An isosceles trapezium (isosceles triangle with its apex removed) would have congruent diagonals but it is not a parallelogram.