Question

Rezolvati ecuatia 1/5^x=25^(-2).

Answer 1

1/5 ^x = 1/(5^2)^2
1/5^x = 1/5^4 
x = 4 

Answer 2

$\it \dfrac{1}{5^x} =25^{-2} \Leftrightarrow 5^{-x} =(5^2)^{-2} \Leftrightarrow 5^{-x} =5^{-4} \Longrightarrow x = 4$