It could be a trapezoid.
Because there are only two right angles, it can't be a square or a rectangle.
Because there are no equal length sides, it's not a parallelogram at all.
A trapezoid is a quadrilateral, and none of the sides need to be the same length. The shape could be this: think of a really long rectangle, but slice off one side of it at a 45 degree angle and put a line where you sliced.