document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1163889>Question 1163889</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question: The first term of an arithmetic sequence is 2; and the first, third, and eleventh terms are also the first three terms of a geometric sequence. Find the sum of the first eleven terms of the arithmetic sequence.\r<BR>\n" );
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document.write( "How far I got:<BR>\n" );
document.write( "   The third term of AP: 2+2d which is equal to second term of GP 2r giving<BR>\n" );
document.write( "   equation (1)......  2 + 2d - 2r = 0<BR>\n" );
document.write( "   Likewise, the 11th term of AP: 2+10d is equal to third term of GP 2r^2 giving<BR>\n" );
document.write( "   equation (2)......  2 + 10d - 2r^2 = 0<BR>\n" );
document.write( "   Solving the system I get, r = 1 and 4 (discard 1 as it is GP) and d = 3<BR>\n" );
document.write( "   So the sum of AP is (34/2)= 17.<BR>\n" );
document.write( "Obviously I am wrong. Can you please point it out.<BR>\n" );
document.write( "Please dont give me the answer. Just give me the broad steps to solve the problem.<BR>\n" );
document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #788134 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=788134\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Your steps are fine.<br><BR>\n" );
document.write( "Your initial equations are fine.<br><BR>\n" );
document.write( "Your solution to the system of equations is not right.<br><BR>\n" );
document.write( "Since you didn't show the work you did to solve the system of equations, we can't point out your error.  You should be able to find it yourself.<br><BR>\n" );
document.write( "Don't try to look at your previous work and see what was wrong with it; when you try to do that, you often end up making the same mistake.<br><BR>\n" );
document.write( "Start over with your two equations an try solving them anew.<br><BR>\n" );
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document.write( "I misread your solution; your answers r=4 and d=3 are correct.<br><BR>\n" );
document.write( "What is wrong is your final answer to the question as to the sum of the first 11 terms of the arithmetic sequence.<br><BR>\n" );
document.write( "That sum is the average of the first and eleventh terms (which you show), MULTIPLIED BY the number of terms (11).<br><BR>\n" );
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