document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=190034>Question 190034</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780395977255/algebrahomeworkh>algebra and trigonometry structure and method book 2</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Let a, b, c and d be positive. Prove the following properties of the proportion a/b=c/d. ( Hint: For exercises 13-16, multiply both sides of a/b=c/d by an expression that will produce the given equation.)\r<BR>\n" );
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document.write( "d/b=c/a\r<BR>\n" );
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document.write( "please explain and thank you so much.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #142609 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=142609\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> So you're trying to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2Fb=c%2Fa ALIGN=MIDDLE  ALT=\"d%2Fb=c%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" > from <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb=c%2Fd ALIGN=MIDDLE  ALT=\"a%2Fb=c%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" >???\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb=c%2Fd ALIGN=MIDDLE  ALT=\"a%2Fb=c%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given equation<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%28a%2Fb%29=cross%28d%29%28c%2Fcross%28d%29%29 ALIGN=MIDDLE  ALT=\"d%28a%2Fb%29=cross%28d%29%28c%2Fcross%28d%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply both sides by \"d\"\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28ad%29%2Fb=c ALIGN=MIDDLE  ALT=\"%28ad%29%2Fb=c\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28cross%28a%29%2Ad%29%2F%28cross%28a%29%2Ab%29=c%2Fa ALIGN=MIDDLE  ALT=\"%28cross%28a%29%2Ad%29%2F%28cross%28a%29%2Ab%29=c%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by \"a\"\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2Fb=c%2Fa ALIGN=MIDDLE  ALT=\"d%2Fb=c%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify </SPAN>\n" );
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