bantuin yang ini donk teman, sama caranya y

log (2a-2) = 1
log (2a-2) = log10
2a - 2 = 10
2a = 12
a = 6

log (b-4) = log a
log (b-4) = log 6
b-4 = 6
b = 10

xlog a =log b
xlog 6 = log 10
xlog 6 = 1
x^1 = 6
x = 6
x - 1/x = 6 - 1/6 = 5 5/6
Jawaban A