Answer:
x = 8
Step-by-step explanation:
[tex] {25}^{(x - 20)} = \frac{1}{ {125}^{x} } \\ \\ {5}^{2(x - 20)} = \frac{1}{ {5}^{3x} } \\ \\ {5}^{2x - 40} = {5}^{ - 3x} \\ \\ 2x - 40 = - 3x ..(bases \: are \: equal \: \\ therefore \: exponents \: will \: also \: be \: equal)\\ 2x + 3x = 40 \\ 5x = 40 \\ x = \frac{40}{5} \\ \huge \purple{ \boxed{ x = 8}}[/tex]
