document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=933534>Question 933534</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The first difference of a sequence is 3, 9, 15, 21,... The sum of the first two terms of the original sequence is 21. Find the first three terms of the original sequence. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #566883 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20056)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=566883\">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=a%5B2%5D-a%5B1%5D=3 ALIGN=MIDDLE  ALT=\"a%5B2%5D-a%5B1%5D=3\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B3%5D-a%5B2%5D=9 ALIGN=MIDDLE  ALT=\"a%5B3%5D-a%5B2%5D=9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B4%5D-a%5B3%5D=15 ALIGN=MIDDLE  ALT=\"a%5B4%5D-a%5B3%5D=15\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B5%5D-a%5B4%5D=21 ALIGN=MIDDLE  ALT=\"a%5B5%5D-a%5B4%5D=21\"   DISABLED_style= \"max-width:90%; height:auto;\" >,\r<BR>\n" );
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document.write( "3, 9, 15, 21\r<BR>\n" );
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document.write( "Since we are given that \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B2%5D%2Ba%5B1%5D=21 ALIGN=MIDDLE  ALT=\"a%5B2%5D%2Ba%5B1%5D=21\"   DISABLED_style= \"max-width:90%; height:auto;\" >, we have the system\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28a%5B2%5D-a%5B1%5D=3%2Ca%5B2%5D%2Ba%5B1%5D=21%29 ALIGN=MIDDLE  ALT=\"system%28a%5B2%5D-a%5B1%5D=3%2Ca%5B2%5D%2Ba%5B1%5D=21%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solve that system and get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B2%5D=12 ALIGN=MIDDLE  ALT=\"a%5B2%5D=12\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B1%5D=9 ALIGN=MIDDLE  ALT=\"a%5B1%5D=9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B3%5D-a%5B2%5D=9 ALIGN=MIDDLE  ALT=\"a%5B3%5D-a%5B2%5D=9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B3%5D-12=9 ALIGN=MIDDLE  ALT=\"a%5B3%5D-12=9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B3%5D=21 ALIGN=MIDDLE  ALT=\"a%5B3%5D=21\"   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%5B4%5D-a%5B3%5D=15 ALIGN=MIDDLE  ALT=\"a%5B4%5D-a%5B3%5D=15\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B4%5D-a%5B3%5D=15 ALIGN=MIDDLE  ALT=\"a%5B4%5D-a%5B3%5D=15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B4%5D-21=15 ALIGN=MIDDLE  ALT=\"a%5B4%5D-21=15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B4%5D=36 ALIGN=MIDDLE  ALT=\"a%5B4%5D=36\"   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%5B5%5D-a%5B4%5D=21 ALIGN=MIDDLE  ALT=\"a%5B5%5D-a%5B4%5D=21\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B5%5D-36=21 ALIGN=MIDDLE  ALT=\"a%5B5%5D-36=21\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B5%5D=57 ALIGN=MIDDLE  ALT=\"a%5B5%5D=57\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The general term, BTW, is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%28n%5E2-2n%2B4%29 ALIGN=MIDDLE  ALT=\"3%28n%5E2-2n%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Edwin\r<BR>\n" );
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document.write( " </SPAN>\n" );
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