document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=370783>Question 370783</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve by factoring and using the principle of zero products:<BR>\n" );
document.write( " x^2 + 4x - 21 = 0<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 #264535 by </B><A HREF=/tutors/aboutme.mpl?userid=jsmallt9><B>jsmallt9(3758)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jsmallt9><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=264535\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+4x+-+21+=+0 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+4x+-+21+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Just as the problem says, factor:<BR>\n" );
document.write( "(x + 7)(x - 3) = 0<BR>\n" );
document.write( "From the Zero Product Property we know that this (or any) product can be zero <i>only</i> if one (or more) of the factors is zero. So:<BR>\n" );
document.write( "x+7 = 0 or x-4 = 0<BR>\n" );
document.write( "Solving these we get:<BR>\n" );
document.write( "x = -7 or x = 4 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );