The real x and y satisfying simultaneously log8x + log4y2 = 5log8y + log4x2 = 7, then the value of xy equal to -(A) 29 (B) 212 (C) 218 (D) 224

Note: Recheck your optionsGiven that, log8x+log4y2=5log8y+log4x2=7So,log8x+log4y2=7log23x+log22y2=713log2x+12log2y2=7log2x13+log2y212=7log2x13y212=7log2x13y=7x13y=27xy3=221      .....1And,5log8y+log4x2=75log23y+log22x2=753log2y+12log2x2=7log2y53+log2x212=7log2y53x212=7log2y53x=7y53x=27y5x3=221      .....2Equating equation2and 1,y2x2=1xy=±1

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