Question

\(5^{2x-3}-2.5^2=5^2.3\)

Tìm số tự nhiên x , biết

Answer 1

\(5^{2x-3}-2.5^2=5^2.3\)

\(\Rightarrow5^{2x-3}=5^2.3+5^2.2\)

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

\(\Rightarrow2x-3=3\)

\(\Rightarrow2x=6\)

\(\Rightarrow x=3\)

Answer 2

\(5^{2x-3}\)-2.\(5^2\)= \(5^2\).3

\(5^{2x-3}\) _2.25=25.3

\(5^{2x-3_{ }}\)_50=75

\(5^{2x-3}\)= 75_50

\(5^{2x-3}\)= \(5^2\)

suy ra : 2x-3=2

2x=2.3

2x=6

x=6:2

x=3