Explanation

Given:

log₈₁ 9 = x

We can rewrite this in exponential form:

81^x = 9

Since 81 = 9², we can rewrite:

(9²)^x = 9

9^(2x) = 9¹

Equating the exponents:

2x = 1

x = 1/2

x = 0.5