Let's solve the equations one by one:

(5 2/3 - 1,6) - x = 6 1/3
First, convert the mixed numbers to improper fractions:
(17/3 - 6/3) - x = 19/3
(11/3) - x = 19/3
-x = 19/3 - 11/3
-x = 8/3
x = -8/3

x - (-4,6 + 3 4/7) = -8 1/14
First, convert the mixed numbers to improper fractions:
x - (-28/7 + 31/7) = -115/14
x - (3/7) = -115/14
x = -115/14 + 3/7
x = -230/14 + 6/14
x = -224/14
x = -16

Therefore, the solutions are:
x = -8/3
x = -16