document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=7015>Question 7015</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the 12th term of an arithmatic series is 42 and the sum of the first 17 terms is 51. find the common difference of the series and the first three terms. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #3853 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=3853\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 12th term is a+11d = 42 --eqn1.\r<BR>\n" );
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document.write( "Formula for summation is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5Bn%5D ALIGN=MIDDLE  ALT=\"S%5Bn%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28n%2F2%29%282a+%2B+%28n-i%29d%29 ALIGN=MIDDLE  ALT=\"%28n%2F2%29%282a+%2B+%28n-i%29d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so as <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B17%5D ALIGN=MIDDLE  ALT=\"S%5B17%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 51 we get:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B17%5D ALIGN=MIDDLE  ALT=\"S%5B17%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2817%2F2%29%282a+%2B+%2817-i%29d%29 ALIGN=MIDDLE  ALT=\"%2817%2F2%29%282a+%2B+%2817-i%29d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 51\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2817%2F2%29%282a+%2B+16d%29+=+51 ALIGN=MIDDLE  ALT=\"%2817%2F2%29%282a+%2B+16d%29+=+51\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2a+%2B+16d+=+6 ALIGN=MIDDLE  ALT=\"2a+%2B+16d+=+6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "--> a+8d = 3 --eqn2\r<BR>\n" );
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document.write( "Solve eqn1 and 2 simultaneously to get a and d. -101 and 13\r<BR>\n" );
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document.write( "jon.<BR>\n" );
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