Answer:
is not a rectangle
Explanation:
The midpoints of the diagonals are ...
AC midpoint = ((2, -2) +(11, 13))/2 = (13/2, 11/2)
BD midpoint = ((14, 10) +(-2, 1))/2 = (6, 11/2)
The midpoints of the diagonals are different, so this is not a rectangle or any sort of parallelogram.