Question

25 elevado a x-1=1/125 (um sobre 125)

Answer 1

${25}^{x - 1} = \frac{1}{125} \\ { ({5}^{2}) }^{x - 1} = \frac{1}{ {5}^{3} } \\ {5}^{2x - 2} = {5}^{ - 3} \\ 2x - 2 = - 3$

$2x = 2 - 3 \\ 2x = - 1 \\ x = - \frac{1}{2}$