Question 1003068
Original dimensions w and L for width and length.
Area A=wL
Perimeter p=2w+2L


New rectangle is of dimensions L+1 and w-1.
Area  (L+1)(w-1)
wL+w-L-1
Or you could refer to A from the original rectangle and say new area is A+w-L-1.


New perimeter  2(w-1)+2(L+1)
2w-2+2L+2
2w+2L
This is the same perimeter as the original perimeter.