document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=259646>Question 259646</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Solve using the principle of zero products.\r<BR>\n" );
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document.write( "(21 - 0.8x)(5 - 0.4x) = 0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #191080 by </B><A HREF=/tutors/aboutme.mpl?userid=unlockmath><B>unlockmath(1688)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=unlockmath><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=unlockmath><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=191080\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hello, <BR>\n" );
document.write( "Since this has been factored out (21 - 0.8x)(5 - 0.4x) = 0 we can solve both x's.<BR>\n" );
document.write( "(21 - 0.8x)=0 Subtract 21 from both sides to give us:<BR>\n" );
document.write( "-.8x=-21 Divide both sides by -.8 to be:<BR>\n" );
document.write( "x=26.25 Now let's do the other x<BR>\n" );
document.write( "(5 - 0.4x) = 0 Subtract 5 from both sides to be:<BR>\n" );
document.write( "-.4x=-5 Divide both sides by -.4 to be:<BR>\n" );
document.write( "x=12.5<BR>\n" );
document.write( "Plug these answers into the original to see if it works. <BR>\n" );
document.write( "RJ <BR>\n" );
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document.write( "www.math-unlock.com </SPAN>\n" );
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