(1/25)x+2=(125)2x+4adalah

(1/25)^(x+2) = (125)^(2x+4.
(1/5)^2(x+2) = (5)^3(2x+4)
(5)^-2x-4 = (5)^6x+12
-2x - 4 = 6x + 12
8x = - 16. maka x = - 2.