By property of rectangle, opposite sides are equal.
⇒Lengths are equal i.e., CD = AB
⇒ x+3y=13...(i)
Breadth are equal i.e., AD = BC
⇒ 3x+y=7...(ii)
On multiplying Eq (ii) by 3 and then subtracting Eq. (i), we get
9x+3y=21x+3y=13 –––––––––––––8x =8
x = 1
On putting x=1 in Eq. (i), we get
3y=12 ⇒ y=4
Hence, the required values of x and y are 1 and 4, respectively.