первое число Х, второе число У
xy = 20
y=20/x
(x-1.6)*y = 16
(x-1,6)*(20/x) = 16
(x - 1.6) * 20
----------------- = 16
1 * x
20x - 32
------------ = 16
x
20x - 32 = 16x
20x-16x = 32
4x = 32
x = 8
y = 20/x
y = 20/8
y = 2.5
8*2.5 = 20
(8 - 1.6) * 2.5 = 16