\(a,5x+4^3:16=49\)
\(5x+4=49\)
\(\Rightarrow5x=45\)
\(\Rightarrow x=9\)
\(b,2^x+5.2^x=6.2^7\)
\(2^x\left(1+5\right)=6.2^7\)
\(2^x.6=6.2^7\)
\(\Rightarrow x=7\)
a)\(5.x+4^3\div16=49\)
\(\Leftrightarrow5x+4^3\div4^2=49\)
\(\Leftrightarrow5x+4=49\)
\(\Leftrightarrow5x=45\Rightarrow x=9\)
Vậy x= 9
b)\(2^x+5.2^x=6.2^7\)
\(2^x\left(1+5\right)=6.2^7\)
\(2^x.6=6.2^7\Rightarrow2^x=2^7\Rightarrow x=7\)
Vậy x=7
5.x+4^3=49
5.x+64:16=49
5.x+4=49
5.x=49-4
5.x=45
x=45:5
x=9
a) 5.x + 43 : 16 = 49
=> 5.x + 43 : 42 = 49
=> 5.x + 4 = 49
=> 5.x = 45
=> x = 5
b) 2x +5. 2x = 6. 27
=> 2x.(1+5) = 3.2.27
=> 2x. 6 = 3. 28
=> 2x.2.3 = 3. 28
=> 2x+1 .3 = 3. 28
=> 2x+1 = 28
=> x+1 = 8
=> x = 7
Tìm x :
a) 5 . x + 4^3 : 16 = 49
<=> 5 . x + 4^3 : 4^2 = 49
<=> 5 . x + 4^1 = 49
<=> 5 . x + 4 = 49
<=> 5 . x = 49 - 4
<=> 5 . x = 45
<=> x = 45 : 5
<=> x = 9
Vậy x = 9
b) 2^x + 5 . 2^x = 6 . 2^7
<=> 2^x . 1 + 5 . 2^x = 6 . 128
<=> 2^x . ( 1 + 5 ) = 6 . 128
<=> 2^x . 6 = 6 . 128
<=> 2^x = 6 . 128 : 6
<=> 2^x = ( 6 : 6 ) . 128
<=> 2^x = 128
<=> 2^x = 2^7
=> x = 7
Vậy x = 7
