document.write( "Question 625447: Please help me solve this equation
\n" ); document.write( " 16^2k= 4^k-1\r
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\n" ); document.write( "and (x^1/4-6 )(x^1/2-3) = 0
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Algebra.Com's Answer #393581 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
I assume that you meant \"16%5E%282k%29=+4%5E%28k-1%29\".
\n" ); document.write( "Since \"16=4%5E2\", we can write it as
\n" ); document.write( "\"%284%5E2%29%5E%282k%29=+4%5E%28k-1%29\"
\n" ); document.write( "Using the properties of powers, we can transform that equation into a friendlier one.
\n" ); document.write( "\"%284%5E2%29%5E%282k%29=+4%5E%28k-1%29\" --> \"4%5E%282%2A2%2Ak%29=+4%5E%28k-1%29\" --> \"4%5E%284k%29=+4%5E%28k-1%29\"
\n" ); document.write( "Since \"4%5Ek\" cannot be zero, we can divide by \"4%5Ek\" both sides of the equal sign to get
\n" ); document.write( "\"4%5E%284k%29%2F4%5Ek=+4%5E%28k-1%29%2F4%5Ek\"
\n" ); document.write( "Now we keep using properties of powers
\n" ); document.write( "\"4%5E%284k%29%2F4%5Ek=+4%5E%28k-1%29%2F4%5Ek\" --> \"4%5E%284k-k%29=4%5E%28k-1-k%29\" --> \"4%5E%283k%29=4%5E%28-1%29\" --> \"3k=-1\" --> \"highlight%28k=-1%2F3%29\"
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\n" ); document.write( "I understand that your other equation is \"%28x%5E%281%2F4%29-6+%29%28x%5E%281%2F2%29-3%29+=+0\" or \"%28x%5E0.25-6+%29%28x%5E0.5-3%29+=+0\"
\n" ); document.write( "(I cannot get those nasty fractional exponents to show themselves nicely).
\n" ); document.write( "For that equation , I would just start by doing a change of variable, to get rid of those nasty fractional exponents.
\n" ); document.write( "I can define \"y=x%5E%281%2F4%29=x%5E0.25\" <--> \"x=y%5E4\" and then \"y%5E2=x%5E%281%2F2%29=x%5E0.5\"
\n" ); document.write( "I re-write the equation as
\n" ); document.write( "\"%28y-6%29%28y%5E2-3%29=0\"
\n" ); document.write( "I cannot use the solution \"y=-sqrt%283%29\" because \"y=x%5E%281%2F4%29=x%5E0.25%3E=0\"
\n" ); document.write( "The other two y solutions give me good x solutions
\n" ); document.write( "\"y=6\" --> \"x=6%5E4\" --> \"x=1296\" and
\n" ); document.write( "\"y=sqrt%283%29\" --> \"x=%28sqrt%283%29%29%5E4\" --> \"x=9\"
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