document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=863271>Question 863271</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find 'n'<BR>\n" );
document.write( "1+3+...+2n-1=10(4n+50) <BR>\n" );
document.write( "Do I have to do something with (2n-1+2)(2n-1)<BR>\n" );
document.write( "I have no idea. Please help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #520291 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=520291\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The sum of n consecutive odd integers is given by the following formula<BR>\n" );
document.write( "Sn = (n/2)(2x1 + 2n - 2)  where x1 is the first integer in the sequence<BR>\n" );
document.write( "in our example x1 is 1, therefore we have<BR>\n" );
document.write( "10(4n+50) = (n/2)(2 +2n -2)<BR>\n" );
document.write( "40n+500 = 2n^2 / 2<BR>\n" );
document.write( "n^2 -40n -500 = 0<BR>\n" );
document.write( "(n-50)(n+10) = 0<BR>\n" );
document.write( "n is 50 or -10<BR>\n" );
document.write( "in our case n = 50 is the required answer<BR>\n" );
document.write( " </SPAN>\n" );
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