Nomer 13 tolong dong

6^(x - 1) = (2/3)^(x + 1)
2^(x - 1) . 3^(x - 1) = 2^(x + 1) / 3^(x + 1)
3^(x - 1) . 3^(x + 1) = 2^(x + 1) / 2^(x - 1)
3^(x - 1 + x + 1) = 2^(x + 1 - x + 1)
3^2x = 2^2
2x . log 3 = log 4
x = 1/2 . ³log 4
x = ³log 2