document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=141026>Question 141026</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, I have done this problem in solving equation:<BR>\n" );
document.write( "2^2 – x – 1 = 0<BR>\n" );
document.write( "This is how I did the problem<BR>\n" );
document.write( "Factor the equation: (2x + 1) (x – 1) = 0<BR>\n" );
document.write( "Factor separately to equal 0: 2x + 1= 0 x – 1 = 0<BR>\n" );
document.write( "2x = -1 x = 1<BR>\n" );
document.write( "x  = - ½\r<BR>\n" );
document.write( "\n" );
document.write( "My question is how to check the answer, and to go back to original equation? <BR>\n" );
document.write( "I hope some one can help me please I am not sure about how to go back to the original equation. Thank you very much.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #102663 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=102663\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2x^2 – x – 1 = 0<BR>\n" );
document.write( "2x^2-2x+x-1 = 0<BR>\n" );
document.write( "2x(x-1)+(x-1) = 0<BR>\n" );
document.write( "(x-1)(2x+1) = 0<BR>\n" );
document.write( "x-1 = 0 or 2x+1 = 0<BR>\n" );
document.write( "x = 1 or x = -1/2<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "Checking:<BR>\n" );
document.write( "x=1:<BR>\n" );
document.write( "2*1^2 - 1 -1 = 0<BR>\n" );
document.write( "2-1-1 = 0<BR>\n" );
document.write( "0=0<BR>\n" );
document.write( "----------<BR>\n" );
document.write( "x=-1/2<BR>\n" );
document.write( "2(-1/2)^2-(-1/2)-1 = 0<BR>\n" );
document.write( "2(1/4) + 1/2 - 1 = 0<BR>\n" );
document.write( "1/2 + 1/2 - 1 = 0<BR>\n" );
document.write( "1 - 1 = 0<BR>\n" );
document.write( " 0 = 0<BR>\n" );
document.write( "===============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );