SOLUTION: If log[16]x+log[4]x+log[2]x=7, then x=???

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Question 647299: If log[16]x+log[4]x+log[2]x=7, then x=???

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

log[16]x+log[4]x+log[2]x=7

Note: log%2816%2Cx%29+=+log%282%2Cx%29%2Flog%282%2C16%29=+log%282%2Cx%29%2F4 &log%284%2Cx%29+=+log%282%2Cx%29%2Flog%282%2C4%29=+log%282%2Cx%29%2F2

log%282%2Cx%29%2F4+%2B+log%282%2Cx%29%2F2+%2B+log%282%2Cx%29+=+7 |Multiplying thru by 28 so as all denominators = 1

 49%2Alog%282%2Cx%29+=+196

  log%282%2Cx%29+=+4

   2%5E4+=+x+=+16