\(5^x+5^{x+2}=650\)
\(\Rightarrow5^x+5^x\cdot5^2=650\)
\(\Rightarrow5^x\left(1+5^2\right)=650\)
\(\Rightarrow5^x\cdot26=650\)
\(\Rightarrow5^x=25\)
\(\Rightarrow5^x=5^2\Rightarrow x=2\)
\(5^x+5^{x+2}=650\)
\(\Rightarrow5^x+5^x.5^2=650\)
\(\Rightarrow5^x\left(1+5^2\right)=650\)
\(\Rightarrow5^x.26=650\)
\(\Rightarrow5^x=25\)
\(\Rightarrow5^x=5^2\)
\(\Rightarrow x=2\)
Vậy \(x=2\)
5x +5x . 52 =650
5x . ( 52 + 1) = 650
5x . 26 =650
5x =650/26
5x =25
5x =52
x =2
vậy x = 2