document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1116106>Question 1116106</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I'm trying to brush up on my math skills 45 years after high school.  Most of it is pretty basic but this one has me stumped.\r<BR>\n" );
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document.write( "( b + a ) / ab = 1 / f<BR>\n" );
document.write( "solve for b\r<BR>\n" );
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document.write( "I've mashed it all around but I just can't tease out the b.  I even tried working backward from the answer.  How is this done?  The answer in the back of the book is:\r<BR>\n" );
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document.write( "b = fa / ( a - f ) or b = -fa / ( f - a )\r<BR>\n" );
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document.write( "if you're interested.\r<BR>\n" );
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document.write( "Thank you,<BR>\n" );
document.write( "Jim </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #730935 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10552)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=730935\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "I'm trying to brush up on my math skills 45 years after high school.  Most of it is pretty basic but this one has me stumped.\r<BR>\n" );
document.write( "\n" );
document.write( "( b + a ) / ab = 1 / f<BR>\n" );
document.write( "solve for b\r<BR>\n" );
document.write( "\n" );
document.write( "I've mashed it all around but I just can't tease out the b.  I even tried working backward from the answer.  How is this done?  The answer in the back of the book is:\r<BR>\n" );
document.write( "\n" );
document.write( "b = fa / ( a - f ) or b = -fa / ( f - a )\r<BR>\n" );
document.write( "\n" );
document.write( "if you're interested.\r<BR>\n" );
document.write( "\n" );
document.write( "Thank you,<BR>\n" );
document.write( "Jim<BR>\n" );
document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\"><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%281%2C3%2C+%28b+%2B+a%29%2Fab%2C+%22=%22%2C+1%2Ff%29 ALIGN=MIDDLE  ALT=\"matrix%281%2C3%2C+%28b+%2B+a%29%2Fab%2C+%22=%22%2C+1%2Ff%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "ab = f(b + a) ------ Cross-multiplying<BR>\n" );
document.write( "ab = bf + af<BR>\n" );
document.write( "ab - bf = af<BR>\n" );
document.write( "b(a - f) = af<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28matrix%281%2C3%2C+b%2C+%22=%22%2C+af%2F%28a+-+f%29%29%29 ALIGN=MIDDLE  ALT=\"highlight_green%28matrix%281%2C3%2C+b%2C+%22=%22%2C+af%2F%28a+-+f%29%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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