document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=830793>Question 830793</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The first term of sequnce is x. To get the next term multiply the previous term by 2 and add 1.the third term of the sequence is 21.find the value of x. Plzz help me find the answer...its 4.5 in the book gcse  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #500959 by </B><A HREF=/tutors/aboutme.mpl?userid=JulietG><B>JulietG(1812)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=JulietG><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=JulietG><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=500959\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Your sequence is:\r<BR>\n" );
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document.write( "(x, 2x + 1, 21)<BR>\n" );
document.write( "You can work this backward.<BR>\n" );
document.write( "Find the middle number first.<BR>\n" );
document.write( "21 - 1 = 2x<BR>\n" );
document.write( "20 = 2x<BR>\n" );
document.write( "10 = x<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Now take the 10 and work backward with the same formula.<BR>\n" );
document.write( "10 - 1 = 2x<BR>\n" );
document.write( "9 = 2x<BR>\n" );
document.write( "4.5 = x<BR>\n" );
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document.write( "Let's plug it in to make certain.<BR>\n" );
document.write( "4.5 * 2 = 9, plus 1 = 10<BR>\n" );
document.write( "10 * 2 = 20, plus 1 = 21<BR>\n" );
document.write( "Success! </SPAN>\n" );
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