85 . 4x = 221
215 . 4x = 221
4x = 221 : 215
4x = 26
4x = 64
x = 64 : 4
x = 16
\(8^5\cdot4x=2^{21}\)
\(\Rightarrow2^{15}\cdot4x=2^{21}\)
\(\Rightarrow4x=2^6\)
\(\Rightarrow4x=64\)
\(\Rightarrow x=16\)
85 . 4x = 221
85 . 4x = ( 23 ) 7
85 . 4x = 87
4x = 82
x = 16
Chúc bn hc tốt <3
85 . 4x = 221
85 . 4x = ( 23 ) 7
85 . 4x = 87
4x = 87 : 85 = 82
x = 16
Vậy x = 16
\(8^5.4x=2^{21}\)
\(2^{15}.4x=2^{21}\)
\(4x=2^6\)
\(4x=64\)
\(x=64:4=16\)
85 . 4x = 221
85 . 4x = ( 23 )7
85 . 4x = 87
4x = 87 : 85
4x = 82
4x = 64
x = 64 : 4
x = 16
85 . 4x = 221
85 . 4x = (23)7
85 . 4x = 87
4x = 87 : 85
4x = 82
4x = 64
x = 64 : 4
x = 16
Vậy x = 16