1625xx I need it put in a mathmatical format but i suspect it is a trick question?

Question

i dont understand how it got greater-where is the perimeter

Answer 1

Huh??

Answer 2

and here is the tricky answer:

1625xx

= 1600xx + 25xx

= 40^2xx + 5^xx

= (40xx+5xx)^2 - 2 (40xx)(5xx)

hope it helps :))