document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1169395>Question 1169395</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In this arithmetic sequence wee are given that S1=9 AND S2=20<BR>\n" );
document.write( "What is the 4th terms.<BR>\n" );
document.write( "Thanks for your help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #794083 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=794083\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> So with an AP, you have common differences from one term to the next:<br>\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B1%5D+=+9 ALIGN=MIDDLE  ALT=\"S%5B1%5D+=+9\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+S%5B2%5D=20+ ALIGN=MIDDLE  ALT=\"+S%5B2%5D=20+\"   DISABLED_style= \"max-width:90%; height:auto;\" > means the common difference is 20-9 = 11.<br>\r<BR>\n" );
document.write( "\n" );
document.write( "Therefore <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+S%5Bn%5D+=+9+%2B+11%28n-1%29+ ALIGN=MIDDLE  ALT=\"+S%5Bn%5D+=+9+%2B+11%28n-1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  where n = 1,2,3,...\r<BR>\n" );
document.write( "\n" );
document.write( "Plug in n=4 to find <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+S%5B4%5D+=+42+ ALIGN=MIDDLE  ALT=\"+S%5B4%5D+=+42+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );