document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=190880>Question 190880</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 follwing properties of the proportion a/b=c/d. \r<BR>\n" );
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document.write( "17. a+b/b=c+d/d\r<BR>\n" );
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document.write( "how do i prove this? please help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #143311 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=143311\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If we look at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28a%2Bb%29%2Fb=%28c%2Bd%29%2Fd ALIGN=MIDDLE  ALT=\"%28a%2Bb%29%2Fb=%28c%2Bd%29%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" >, we can see that it breaks down to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb%2Bb%2Fb=c%2Fd%2Bd%2Fd ALIGN=MIDDLE  ALT=\"a%2Fb%2Bb%2Fb=c%2Fd%2Bd%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" > and simplifies to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb%2B1=c%2Fd%2B1 ALIGN=MIDDLE  ALT=\"a%2Fb%2B1=c%2Fd%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" >. So to reverse this, we must add 1 to both sides of <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;\" > and combine the terms. Note: we must start with what we are given to find the unknown (so we must start with the equation <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\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb%2B1=c%2Fd%2B1 ALIGN=MIDDLE  ALT=\"a%2Fb%2B1=c%2Fd%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" > Add 1 to both sides. \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb%2Bb%2Fb=c%2Fd%2B1 ALIGN=MIDDLE  ALT=\"a%2Fb%2Bb%2Fb=c%2Fd%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply the first \"1\" by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%2Fb ALIGN=MIDDLE  ALT=\"b%2Fb\"   DISABLED_style= \"max-width:90%; height:auto;\" > (to make the denominators on the left side equal). \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2Fb%2Bb%2Fb=c%2Fd%2Bd%2Fd ALIGN=MIDDLE  ALT=\"a%2Fb%2Bb%2Fb=c%2Fd%2Bd%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply the second \"1\" by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2Fd ALIGN=MIDDLE  ALT=\"d%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" > (to make the denominators on the right side equal). \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28a%2Bb%29%2Fb=%28c%2Bd%29%2Fd ALIGN=MIDDLE  ALT=\"%28a%2Bb%29%2Fb=%28c%2Bd%29%2Fd\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine the fractions </SPAN>\n" );
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