\(125\cdot5^{x-3}=5^7\)
\(5^3\cdot5^{x-3}=5^7\)
\(5^{3+x-3}=5^7\)
\(5^x=5^7\)
\(x=7\)
125.5x-3=57
<=> 5x-3=57:53
<=> 5x-3=54
=> x-3=4
<=>x=7
Ta có: 125.5x-3=57
\(\Rightarrow\)53.5x-3=57
\(\Rightarrow\)53+x-3=57
\(\Rightarrow\)5x=57
\(\Rightarrow\)x=7
Vậy x=7
125.5x-3=57
52.5x-3=57
5x-3=57:52
5x-3=55
=>x-3=5
x=5+3
x=8
Vậy x=8
125 . 5\(^{x-3}\)=78125
5\(^{x-3}\)=625
x - 3 = 625 : 5
x - 3 =125
x = 125 + 3
x =128
125.5^x-3=5^7
=>5^3.5^x-3=5^7
=>5^x=5^7
=>x=7
Bài làm
125 . 5x - 3 = 57
53 . 5x - 3 = 57
5x - 3 + 3 = 57
=> x = 7
Vậy x = 7
# Học tốt #
\(125.5^{x-3}=5^7\)
\(5^3.5^{x-3}=5^7\)
\(5^{3+x-3}=5^7\)
\(5^x=5^7\)
\(x=7\)
