Choose the One Alternative That Best Completes the Statement or Answers

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
-If $5 ^ { x } = 6$ , what does $5 ^ { - 2 x }$ equal?

A) $- 36$
B) $\frac { 1 } { 12 }$
C) $\frac { 1 } { 36 }$
D) 36