Side = 8m
He increases length by 2m and reduces width by 2m
(a.) New dimensions will be -
Length = 10m and Width = 6m
(b.) Area = length x breadth (or width)
here we will use the special product (x+y) (x-y)
length = (x+y) and width = (x-y)
area = (8+2) x (8-2)
8^(2) - 2^(2)
= 60