Question 1206690
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Answer: <font color=red size=4>x = 8</font>


Work Shown


w = log(x)
v = log(2)


2v = 2*log(2) = log(2^2) = log(4)
4v = 4*log(2) = log(2^4) = log(16)
{{{log(2,(x)) + log(4,(x)) + log(16,(x)) = 21/4}}}


{{{log((x))/log((2))+log((x))/log((4))+log((x))/log((16)) = 21/4}}} Change of base rule


{{{w/v+w/(2v)+w/(4v) = 21/4}}}


{{{(w/v)(1+1/2+1/4) = 21/4}}}


{{{(w/v)(7/4) = 21/4}}}


{{{w/v = (21/4)*(4/7)}}}


{{{w/v = 3}}}


{{{w = 3v}}}


{{{log((x)) = 3*log((2))}}}


{{{log((x)) = log((2^3))}}} 


{{{log((x)) = log((8))}}}


{{{x = 8}}}
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