Question

tìm số tự nhiên

a)\(5^x+5^{x+2}=650\)

Answer 1

\(5^x+5^{x+2}=650\)

\(\Leftrightarrow5^x\left(1+5^2\right)=650\)

\(\Leftrightarrow5^x.26=650\)

\(\Leftrightarrow5^x=25\)

\(\Leftrightarrow x=2\)

Vậy x = 2

Answer 2

5^x + 5^x+2 = 650

=> 5^x + 5^x.5² = 650

=> 5^x.(1 + 5²) = 650

=> 5^x.(1 + 25) = 650

=> 5^x.26 = 650

=> 5^x = 650 : 26

=> 5^x = 25 = 5²

=> x = 2

Answer 3

5^x+5^x+2=650

5^x(1+25)=650

5^x26=650

5^x=650:26

5^x=25

=>5^x=5^5

x=5

Answer 4

x=2