document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1127070>Question 1127070</A>: <I><SPAN STYLE=\"word-break: break-all;\"> x,2x+1,11 are three consecutive terms of an arithmetic sequence. Calculate(i) x.(ii) the 30th term. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #743418 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=743418\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x,2x+1,11 are three consecutive terms of an arithmetic sequence. Calculate(i) x.(ii) the 30th term.<BR>\n" );
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document.write( "x,2x+1,11 are the first three terms of an arithmetic sequence. Calculate(i) x.(ii) the 30th term.<BR>\n" );
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document.write( "x + d = 2x + 1  —>  d = x + 1   (1)<BR>\n" );
document.write( "(2x + 1) + d = 11  —>  d = 10 - 2x  (2)<br>\r<BR>\n" );
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document.write( "Set (1) equal to (2):   x + 1 = 10 - 2x<BR>\n" );
document.write( "                                  3x = 9<BR>\n" );
document.write( "                                    x = 3<br>\r<BR>\n" );
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document.write( "d = x + 1 —>  d = 4<br>\r<BR>\n" );
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document.write( "(i)  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28+x=3+%29+ ALIGN=MIDDLE  ALT=\"highlight%28+x=3+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br>\r<BR>\n" );
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document.write( "(ii) To find an answer, it must be assumed that the three terms given are the FIRST three terms (or at least their position m must be given) of the sequence (the problem statement does not provide sufficient information).  <BR>\n" );
document.write( "      <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5B1%5D+=+3+ ALIGN=MIDDLE  ALT=\"+a%5B1%5D+=+3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "     <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5B2%5D+=+3%2B4+=+7+ ALIGN=MIDDLE  ALT=\"+a%5B2%5D+=+3%2B4+=+7+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "     <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5B3%5D+=+3%2B2%2A4+=+11+ ALIGN=MIDDLE  ALT=\"+a%5B3%5D+=+3%2B2%2A4+=+11+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "       ...<BR>\n" );
document.write( "     <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5Bn%5D+=+3+%2B+%28n-1%29%2A4+ ALIGN=MIDDLE  ALT=\"+a%5Bn%5D+=+3+%2B+%28n-1%29%2A4+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <br>\r<BR>\n" );
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document.write( "Plugging in n=30:<BR>\n" );
document.write( "     <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5B30%5D+=+3+%2B+%2829%29%2A4+=+3%2B116+=+highlight%28+119+%29+ ALIGN=MIDDLE  ALT=\"+a%5B30%5D+=+3+%2B+%2829%29%2A4+=+3%2B116+=+highlight%28+119+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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