document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=550851>Question 550851</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have a polynomial regression and I am trying to build a calculation to solve for x. The equation I am looking at is x^2+x+b=y. I can calculate the y easy enough, but writing an excel formula to determine X has got me beat.\r<BR>\n" );
document.write( "\n" );
document.write( "thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #359206 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=359206\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> this is an application of the quadratic formula\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x^2 + x + (b - y) = 0\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x = {-1 ± [sqrt(1 - 4(b - y))]} / 2\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the ± may generate two values for x; you probably want two equations, one + and one - </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );