document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=976760>Question 976760</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find n if Sn = 63, a1 = 21, and d = -4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #598276 by </B><A HREF=/tutors/aboutme.mpl?userid=FrankM><B>FrankM(1040)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=FrankM><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=FrankM><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=598276\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5Bn%5D=%28n%2F2%29%282a%5B1%5D%2B%28n-1%29d%29 ALIGN=MIDDLE  ALT=\"S%5Bn%5D=%28n%2F2%29%282a%5B1%5D%2B%28n-1%29d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "let's enter what we were given - \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=63=%28n%2F2%29%2842-4%28n-1%29%29 ALIGN=MIDDLE  ALT=\"63=%28n%2F2%29%2842-4%28n-1%29%29\"   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=63=%28n%2F2%29%2846-4n%29%29 ALIGN=MIDDLE  ALT=\"63=%28n%2F2%29%2846-4n%29%29\"   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=126=%2846n-4n%5E2%29%29 ALIGN=MIDDLE  ALT=\"126=%2846n-4n%5E2%29%29\"   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=4n%5E2-46n%2B126=0 ALIGN=MIDDLE  ALT=\"4n%5E2-46n%2B126=0\"   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=2n%5E2-23n%2B63=0 ALIGN=MIDDLE  ALT=\"2n%5E2-23n%2B63=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "I'd use the quadratic equation here, note, the solutions result in 4.5 and 7, but the answer must be an integer. \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=7 ALIGN=MIDDLE  ALT=\"n=7\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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