更新1:
A quadrilateral has vertices A(11, -7), B(9, -4), C(11, -1), and D(13, -4). Quadrilateral ABCD is a ______ -parallelogram with non-perpendicular and non congruent adjacent sides -trapezoid with exactly one pair of parallel sides -rectangle with non congruent adjacent side -rhombus with perpendicular
更新2:
If the vertex C(11, -1) were shifted to the point C′(11, 1), quadrilateral ABC′D would be a _______ -paralellogram with non-perpendicular adjacent sides -kite -square -rhombus with non perpendicular adjacent sides