document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=603323>Question 603323</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve for x and y in the equation:2^(x+4y)=1 and 2^(x+8y)=1/4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #380665 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=380665\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> solve for x and y in the equation:2^(x+4y)=1 and 2^(x+8y)=1/4<BR>\n" );
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document.write( "Take the log of both sides:<BR>\n" );
document.write( "(x+4y)log 2 = log 1<BR>\n" );
document.write( "(x+8y)log 2 = log(1/4)<BR>\n" );
document.write( "The 1st equation gives x = -4y<BR>\n" );
document.write( "Subst. into the 2nd:<BR>\n" );
document.write( "(4y)log 2 = log(1/4)<BR>\n" );
document.write( "y = -1/2<BR>\n" );
document.write( "So x = -4*(-1/2) = 2<BR>\n" );
document.write( "Ans: x=2, y=-1/2 </SPAN>\n" );
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