A = (-1,3)
B = (4,3)
C= (-1,-2)
D=(4,-2)
Using distance formula,
AB^2 = (4- -1)^2 + (3-3)^2 = 25
or AB = 5
Similarly we get,
BD = 5, DC =5 and CA = 5
So AB=BD=DC=CA=5 (Sides)
and AD = 5√2 =BC (diagonals)
Since all the four sides are equal and its diagonals are also equal. So the quadrilateral formed is a square.