a) 5x + 5x+2 = 650
5x+ 5x . 52 = 650
5x . 1 + 5x . 25 = 650
5x . ( 1 + 25 ) = 650
5x . 26 = 650
5x = 650 : 26
5x = 25
5x = 52
=> x = 2
b) 3x-1 + 5.3x-1 = 162
3x-1 . 1 + 5.3x-1 = 162
3x-1 . ( 1 + 5 ) = 162
3x-1 . 6 = 162
3x-1 = 162 : 6
3x-1 = 27
3x-1 = 33
x - 1 = 3
x = 3 + 1
x = 4
a) \(5^x+5^{x+2}=650\)
\(5^x\left(1+25\right)=650\)
\(5^x=25\)
\(x=2\)
b) \(3^{x-1}+5\cdot3^{x-1}=162\)
\(3^{x-1}\left(1+5\right)=162\)
\(3^{x-1}=27\)
\(x=4\)
a) 5x + 5x+2 = 650
5x + 5x . 52 = 650
5x + 5x . 25 = 650
5x . ( 1 + 25 ) = 650
5x . 26 = 650
5x = 650 : 26
5x = 25
5x = 52
=> x = 2
Vậy x = 2
b) 3x-1 + 5.3x-1 = 162
3x-1 . ( 5 + 1 ) = 162
3x-1 . 6 = 162
3x-1 = 162 : 6
3x-1 = 27
3x-1 = 33
=> x - 1 = 3
x = 3 + 1
x = 4
Vậy x = 4
a,\(5^x+5^{x+2}=650\)
\(=>5^x+5^x.5^2=650\)
\(=>5^x.\left(5^2+1\right)=650\)
\(=>5^x.26=650\)
\(=>5^x=650:26=25=5^2\)
\(=>x=2\)
b,\(3^{x-1}+5.3^{x-1}=162\)
\(=>3^{x-1}.\left(5+1\right)=162\)
\(=>3^{x-1}=27=3^{4-1}\)
\(=>x=4\)
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\(a,\)\(5^x+5^{x+2}=650\)
\(5^x+5^x.5^2\)\(=650\)
\(5^x.\left(1+25\right)=650\)
\(5^x.26=650\)
\(5^x=25\)
\(5^x=5^2\)
\(\Rightarrow x=2\)
Vậy \(x=2\)
\(b,\)\(3^{x-1}+5.3^{x-1}=162\)
\(3^{x-1}.\left(1+5\right)=162\)
\(3^{x-1}.6=162\)
\(3^{x-1}=27\)
\(3^{x-1}=3^3\)
\(\Rightarrow x-1=3\)
\(\Rightarrow x=4\)
Vậy \(x=4\)
\(a,5^x\left(1+5^2\right)=650\) \(\Rightarrow5^x.26=650\)
\(\Rightarrow5^x=650\div26=25=5^2\)\(\Rightarrow x=2\)
\(b,3^{x-1}\left(1+5\right)=162\Rightarrow3^{x-1}.6=162\)
\(\Rightarrow3^{x-1}=162\div6=27=3^3\)
\(\Rightarrow x-1=3\Rightarrow x=4\)
VẬY : a, x=2 b, x=4
