The coordinates of the vertices of quadrilateral ABCD are A(−5, 1) , B(−2, 5) , C(5, 3) , and D(2, −1) .

(The spaces that need to be filled are where the ?'s are.)

The slope of AB¯¯¯¯¯ is (?) , the slope of BC¯¯¯¯¯ is (?) , the slope of CD¯¯¯¯¯ (?) is , and the slope of AD¯¯¯¯¯ (?) is . Quadrilateral ABCD is (?) because (?).

Choices:
-2/7
-1/3
3/2
4/3
a parallelogram
a trapezoid
neither a parallelogram nor a trapezoid
both pairs of opposite sides are parallel
only one pair of opposite sides is parallel
neither pair of opposite sides is parallel