The 3^0 in the denominator is equal to 1. Any nonzero number raised to an exponent of 0 is always 1. So this equation x^0 = 1 is true when x is nonzero.
This allows us to simplify to the equation 3^x = 1/81
Note how 81 = 3^4. Taking the reciprocal of 81 means the exponent goes from positive to negative. So 3^(-4) = 1/81. The rule is x^(-k) = 1/( x^k ). We could use logarithms to solve 3^x = 1/81.
