The equations of the sides of a parallelogram are x=2,x=3 and  y=1,y=5 .Equations to the pair of diagonals are

The vertices of the parallelogram are  A(2,1),B(2,5),C(3,5) and  D(3,1) Equation of the diagonal AC isy−1=5−13−2(x−2)⇒4x−y=7Equation of the diagonal BD is y−5=1−53−2(x−2)⇒4x+y=13