rhombus
it is a parallelogram or a trapezoid
A pyramid has 4 straIGHT SIDES
It is not clear what you mean by "has 4 right sides opposite sides equal". If you delete the phrase "4 right sides", the answer is a rhombus.
trapezium
That is the description of a square.
square
rhombus
it is a parallelogram or a trapezoid
a Rhombus...
A pyramid has 4 straIGHT SIDES
it has 4 sides
Straight. That is the only requirement which applies to all four sides. In pairs, the sides have to be equal and parallel but that does not apply to all four. In [adjacent] pairs, the sides have to be at right angles, but that does not apply to all 4.
The two states have only four straight sides are Wyoming and Colorado.
It is not clear what you mean by "has 4 right sides opposite sides equal". If you delete the phrase "4 right sides", the answer is a rhombus.
trapezium
A Square