document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=452887>Question 452887</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve for a:\r<BR>\n" );
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document.write( "1/f=1/a+1/b\r<BR>\n" );
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document.write( "I know the answer is a=bf/b-f </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #311277 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=311277\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve for a:\r<BR>\n" );
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document.write( "1/f=1/a+1/b<BR>\n" );
document.write( "1/a = 1/f - 1/b<BR>\n" );
document.write( "1/a = (b - f)/bf [combining the two fractions using the least common denominator bf]<BR>\n" );
document.write( "Taking the reciprocal gives:<BR>\n" );
document.write( "a = bf/(b-f)<BR>\n" );
document.write( " </SPAN>\n" );
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