log4^2 x-6log4 x+5=0

log₁₆x - 6log₄x +5 = 0
log₄x/log₄16 - 6log₄x +5 = 0
1/2*log₄x - 6log₄x + 5 = 0
-5,5log₄x = -5
log₄x = 10/11
х = 4^10/11= ¹¹√4^10