To solve for x in the equation (1/5)^x - 1 = sqrt(5)*5^3, 5 - 4x, we can break down the equation into two parts and solve each part separately.

First, let's solve for x in the equation (1/5)^x - 1 = sqrt(5)5^3:
(1/5)^x - 1 = sqrt(5)5^3
(1/5)^x = sqrt(5)5^3 + 1
(1/5)^x = 55^(3/2) + 1
(1/5)^x = 5^(1/2)*5^3 + 1
(1/5)^x = 5^(1/2 + 3) + 1
(1/5)^x = 5^(7/2) + 1
(1/5)^x = 5^(7/2) + 1
Therefore, x = 7/2.

Next, let's solve for x in the equation 5 - 4x using the value we found in the first equation:
5 - 4x = 5 - 4*7/2 = 5 - 14 = -9.

Therefore, the solution to the equation (1/5)^x - 1 = sqrt(5)*5^3, 5-4x is x = -9.