Question

Resolva as Equação exponenciais 81^6+x=9^-2x

Answer 1

$81^{6+x} = 9^{-2x}\\(9^2)^{6+x} = 9^{-2x}\\9^{2(6+x)} = 9^{-2x}\\2(6+x) = -2x\\12 + 2x = -2x\\4x = -12\\\boxed{x = -3}$