To find the perimeter of a rectangle, you need to know the lengths of its sides. However, the expression you provided does not specify the lengths of the sides. It seems to be a polynomial expression involving variables x and y.
In order to find the perimeter, you would need specific values for x and y. Without those values, it is not possible to calculate the perimeter of the rectangle.
If you have any specific values for x and y or any additional information, please provide them so that I can assist you further in finding the perimeter of the rectangle.