Ta có : 5x - 1 : 5 = 53
=> 5x - 1 = 54
=> x - 1 = 4
=> x = 5
Vậy x = 5
5x-1:5=53
5x-1=53.5
5x-1=54
x-1=4
x=3
\(5^{x-1}:5=125\)
\(5^x:5:5=125\)
\(5^x:1=125\)
\(5^x=125×1\)
\(5^x=125\)
\(5^x=5^3\)
\(x=3\)
vậy x=3
\(5^{x-1}:5=125\)
\(5^{x-1}=125×5\)
\(5^{x-1}=625\)
\(5^{x-1}=5^4\)
x-1=4
x=4+1
x=5
vậy x=5