Measuring number of surface of the rectangle is 128.If we reduce the length of 4 times, then the number is 96cm2.What is the perimeter?
L w = 128 so w = 128/L
(L/4) w = 96
(L/4)(128/L) = impossible so suspect you might mean
L w = 128 so L = 128/w
(L-4) w = 96
(128/w -4) w = 96
128 - 4 w = 96
4 w = 32
w = 8
then L = 128/8 = 16
perimeter = 2*8 + 2*16 = 48