Answer:
D(-7, 2)
Explanation:
The midpoint of diagonal AC is the same as the midpoint of diagonal BD, so ...
(A+C)/2 = (B+D)/2
We can solve for D by multiplying by 2 and subtracting B:
D = A + C - B
D = (-2, 4) +(-4, 1) -(1, 3) = (-2-4-1, 4+1-3)
D = (-7, 2)