document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1109441>Question 1109441</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The 13th and 7th terms of an arithmetic sequence are 15 and 51 respectively <BR>\n" );
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document.write( "Which term is equal to-21?<BR>\n" );
document.write( "Show that 66 is not a term of the sequence </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #724433 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=724433\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> From term #7 to term #13 is six common differences.<BR>\n" );
document.write( "Index 7, term 51.<BR>\n" );
document.write( "Index 13, term 15.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=51%2B6d=15 ALIGN=MIDDLE  ALT=\"51%2B6d=15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6d=15-51 ALIGN=MIDDLE  ALT=\"6d=15-51\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d=-36%2F6 ALIGN=MIDDLE  ALT=\"d=-36%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d=-6 ALIGN=MIDDLE  ALT=\"d=-6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "If first term is A,<BR>\n" );
document.write( "then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A-%28n-1%29%2A6 ALIGN=MIDDLE  ALT=\"A-%28n-1%29%2A6\"   DISABLED_style= \"max-width:90%; height:auto;\" > is general term;<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A-%2813-1%296=15 ALIGN=MIDDLE  ALT=\"A-%2813-1%296=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-12%2A6=15 ALIGN=MIDDLE  ALT=\"A-12%2A6=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=72%2B15 ALIGN=MIDDLE  ALT=\"A=72%2B15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=87 ALIGN=MIDDLE  ALT=\"A=87\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "General Term,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%2887-6%28n-1%29%29 ALIGN=MIDDLE  ALT=\"highlight_green%2887-6%28n-1%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( ".\r<BR>\n" );
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document.write( "********MISTAKE*****MISMATCHED INDICES WITH TERMS****************\r<BR>\n" );
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document.write( "common difference d, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15%2B6%2Ad=51 ALIGN=MIDDLE  ALT=\"15%2B6%2Ad=51\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6d=51-15 ALIGN=MIDDLE  ALT=\"6d=51-15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6d=46 ALIGN=MIDDLE  ALT=\"6d=46\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d=46%2F6=23%2F3 ALIGN=MIDDLE  ALT=\"d=46%2F6=23%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "A, initial term<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2B%28n-1%29%2823%2F3%29 ALIGN=MIDDLE  ALT=\"A%2B%28n-1%29%2823%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, general term<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2B%287-1%29%2823%2F3%29=15 ALIGN=MIDDLE  ALT=\"A%2B%287-1%29%2823%2F3%29=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=15-6%2823%2F3%29 ALIGN=MIDDLE  ALT=\"A=15-6%2823%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=%2845-6%2A23%29%2F3 ALIGN=MIDDLE  ALT=\"A=%2845-6%2A23%29%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=-31 ALIGN=MIDDLE  ALT=\"A=-31\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "General Term:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cross%28-31%2B%28n-1%29%2823%2F3%29%29 ALIGN=MIDDLE  ALT=\"cross%28-31%2B%28n-1%29%2823%2F3%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Which term is  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-21 ALIGN=MIDDLE  ALT=\"-21\"   DISABLED_style= \"max-width:90%; height:auto;\" >?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-31%2B%28n-1%29%2823%2F3%29=-21 ALIGN=MIDDLE  ALT=\"-31%2B%28n-1%29%2823%2F3%29=-21\"   DISABLED_style= \"max-width:90%; height:auto;\" >-------solve for n.\r<BR>\n" );
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document.write( "Is 66 one of the terms?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-31%2B%28n-1%29%2823%2F3%29=66 ALIGN=MIDDLE  ALT=\"-31%2B%28n-1%29%2823%2F3%29=66\"   DISABLED_style= \"max-width:90%; height:auto;\" >-------should find n is NOT an integer and NOT a whole number. </SPAN>\n" );
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