Question

Tìm x \(\in\) N biết :

5^x+4 = 125²

Answer 1

5^x+4 = 125²

<=> 5^x+4 = 5⁶

<=> x + 4 = 6

<=> x = 2

Answer 2

5^x+4 = 125²

\(\Rightarrow\) 5^x+4 = (5³)²

\(\Rightarrow\) 5^x+4 = 5⁶

\(\Rightarrow\) x + 4 = 6

\(\Rightarrow\) x = 2

Answer 3

\(5^{x+4}=125^2\)

\(\Rightarrow5^{x+4}=\left(5^3\right)^2\)

\(\Rightarrow5^{x+4}=5^6\)

\(\Rightarrow x+4=6\)

\(\Rightarrow x=2\)

Vậy \(x=2\)