Answer with explanation:
The Vertices of Rhombus K L MN are , K(a, 0), M(a, b), and N(0, c).
Let Coordinates of Vertices of Point L ,which is one of the vertices among four vertices = (x,y)
As, Diagonals of rhombus bisect each other.
We will use the mid point formula ,to find the vertex of point L.
Mid Point Formula, of line joining two points , (p,q) and (r,s) is

Mid Point of ,K(a,0) and M (a,b) is

Mid Point of L (x,y) and N (0,c) is

As, Diagonal bisect each other,so

Coordinates of vertices of L are =(2 a, b-c)