A quadrilateral has vertices A(11, -7), B(9, -4), C(11, -1), and D(13, -4).

Quadrilateral ABCD is a
. If the vertex C(11, -1) were shifted to the point C′(11, 1), quadrilateral ABC′D would be a
.

If vertex C (11, -1) were shifted to point C' (11, 1), quadrilateral ABC'D would be a trapezoid.