document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1092278>Question 1092278</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if S2 = 10, S10 = 2 then what is a1, d (Arithmetic Sequence)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #706884 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=706884\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Using a for the first term and d for the common difference...<br><BR>\n" );
document.write( "S(2) = a + (a+d) = 2a+d = 10<br><BR>\n" );
document.write( "S(10) = a + (a+d) + (a+2d) + ... + (a+9d) = 10a+45d<br><BR>\n" );
document.write( "So we know<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2a%2Bd+=+10 ALIGN=MIDDLE  ALT=\"2a%2Bd+=+10\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10a%2B45d+=+2 ALIGN=MIDDLE  ALT=\"10a%2B45d+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Multiply the first equation by 5 and subtract the second equation to eliminate variable a, then solve for d.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10a%2B5d+=+50 ALIGN=MIDDLE  ALT=\"10a%2B5d+=+50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40d+=+-48 ALIGN=MIDDLE  ALT=\"40d+=+-48\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+-48%2F40+=+-1.2 ALIGN=MIDDLE  ALT=\"d+=+-48%2F40+=+-1.2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The common difference, d, is -1.2.  Plug this value into one of the earlier equations to solve for a.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2a%2B%28-1.2%29+=+10 ALIGN=MIDDLE  ALT=\"2a%2B%28-1.2%29+=+10\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2a+=+11.2 ALIGN=MIDDLE  ALT=\"2a+=+11.2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+5.6 ALIGN=MIDDLE  ALT=\"a+=+5.6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The first term, a is 5.6.<br><BR>\n" );
document.write( "Answers: first term is 5.6; common difference is -1.2. </SPAN>\n" );
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