document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=68800>Question 68800</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the LCD of<BR>\n" );
document.write( "    7               8<BR>\n" );
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document.write( "a^2 + 2a - 63      a + 9 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #49960 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=49960\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> LCD is the common denominator between each fraction that makes it possible to add and subtract. For instance to add 1/2 and 1/4, the LCD is 4 since 2/4 and 1/4 can be added. For this problem, you need to factor the left fraction first<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%287%29%2F%28a%5E2+%2B+2a+-+63%29 ALIGN=MIDDLE  ALT=\"%287%29%2F%28a%5E2+%2B+2a+-+63%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%287%29%2F%28%28a%2B9%29%28a-7%29%29%29 ALIGN=MIDDLE  ALT=\"%287%29%2F%28%28a%2B9%29%28a-7%29%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > If you FOIL (a+9)(a-7) you get a^2 + 2a - 63<BR>\n" );
document.write( "You will then see that (a+9) is a common factor, so to complete the process, you need to multiply both sides by (a-7)/(a-7). Now you should see the LCD is (a+9)(a-7). </SPAN>\n" );
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