If log_x(27/64) = - 3, then x = ?

A 1/3

B 4/3

C 3/4

D 2/3

Correct Answer: Option B

log_x (27/64) = - 3
⇒ x^{- 3} = 27/64
⇒ x^{- 3} = (3/4)³
⇒ x^{- 3} = 1/(4/3)³
⇒ x^{- 3} = (4/3)^{- 3}
⇒ x = 4/3

If logx(27/64) = - 3, then x = ?