document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1161640>Question 1161640</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The first and the last term of an A.P are 21 and -47 respectively if the sum of the sequence is given is -234, calculate (I)the number of terms in the A.P (ii)the common difference (iii)the sum of the first is term </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #785240 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=785240\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> first term, 21<BR>\n" );
document.write( "last term, -47<BR>\n" );
document.write( "sum of the sequence, -234\r<BR>\n" );
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document.write( "general term, 21+d(n-1)  for d common difference which will be 'negative', and index of term n.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%2821%2Bd%28n-1%29=-47%2C%28n%2F2%29%2821%2B%28-47%29%29=-234%29 ALIGN=MIDDLE  ALT=\"system%2821%2Bd%28n-1%29=-47%2C%28n%2F2%29%2821%2B%28-47%29%29=-234%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Solve this system for n and for d.\r<BR>\n" );
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document.write( "The sum equation solved will give <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=highlight%2818%29 ALIGN=MIDDLE  ALT=\"n=highlight%2818%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or eighteen terms are in the sequence.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28d=-4%29 ALIGN=MIDDLE  ALT=\"highlight%28d=-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, common difference is negative only because the sequence is decreasing.  \r<BR>\n" );
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document.write( "General term <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=21-4%28n-1%29 ALIGN=MIDDLE  ALT=\"21-4%28n-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, another way to show. </SPAN>\n" );
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