Question

Given that log y=log(10x^n).make n the subject of the formula

Answer 1

just recall that exponents and logs are inverse operations, like + and - or * and /.

y = log(10x^n)
10^y = 10x^n
x^n = 10^y/10 = 10^(y-1)
x = 10^{^(y-1)/n}