document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171173>Question 171173</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Will someone please help me.  I don't know where to begin on this problem.  I have to show all my work.<BR>\n" );
document.write( "Find Sn for the arithmetic series in which A1=-11, An=13, and n=7.<BR>\n" );
document.write( "I have a big test later today and really need help.<BR>\n" );
document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #126359 by </B><A HREF=/tutors/aboutme.mpl?userid=monika_p><B>monika_p(71)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=monika_p><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=126359\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Formula for an arithmetic series is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Sn=%28A1+%2B+An%29%2An%2F2 ALIGN=MIDDLE  ALT=\"Sn=%28A1+%2B+An%29%2An%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You have given A1 = -11<BR>\n" );
document.write( "               An = 13<BR>\n" );
document.write( "               n = 7<BR>\n" );
document.write( "substitute and simplify :\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Sn+=+%28-11+%2B+13%29%2A+7%2F2 ALIGN=MIDDLE  ALT=\"Sn+=+%28-11+%2B+13%29%2A+7%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Sn+=+2%2A7%2F2 ALIGN=MIDDLE  ALT=\"Sn+=+2%2A7%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The answer is:<BR>\n" );
document.write( "Sn = 7 </SPAN>\n" );
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