Let the given vertices be A(3, 0), B(4, 5), c(-1, 4) and D(-2, -1)

Here all sides of the quadrilateral ABCD are off same lengths but the diagonals are of different lengths.
So, ABCD is a rhombus.
Therefore area of rhombus ABCD=(1/2)x4√2x6√2
=24 sq. units