document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=186474>Question 186474</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I solved this problem and the teacher says it is wrong. Can you point out what is wrong and help me solve?<BR>\n" );
document.write( "15/3y - (-80/10x)<BR>\n" );
document.write( "5/y +8/x<BR>\n" );
document.write( "13/xy </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #139745 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=139745\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 15/3y - (-80/10x)<BR>\n" );
document.write( "5/y +8/x<BR>\n" );
document.write( "You cannot directly add fractions that have different denominators.\r<BR>\n" );
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document.write( "----<BR>\n" );
document.write( "lcd = xy<BR>\n" );
document.write( "Rewrite each fraction with the lcd as its denominator:\r<BR>\n" );
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document.write( "5x/lcd + 8y/lcd\r<BR>\n" );
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document.write( "Add to get:\r<BR>\n" );
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document.write( "(5x + 8y)/lcd\r<BR>\n" );
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document.write( "= (5x+8y)/xy<BR>\n" );
document.write( "================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );