document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=300396>Question 300396</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve using the 5 step problem solving process. Show all work.\r<BR>\n" );
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document.write( "A number is 72 less than it's square. Find all such numbers. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #215616 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=215616\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A number is 72 less than it's square. Find all such numbers.<BR>\n" );
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document.write( "Let x = \"a number\"<BR>\n" );
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document.write( "x = x^2 - 72<BR>\n" );
document.write( "A quadratic equation<BR>\n" );
document.write( "0 = x^2 - x - 72<BR>\n" );
document.write( "Factors to<BR>\n" );
document.write( "(x-9)(x+8) = 0<BR>\n" );
document.write( "x = +9<BR>\n" );
document.write( "and<BR>\n" );
document.write( "x = -8<BR>\n" );
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document.write( "Check both solution in original equation<BR>\n" );
document.write( "x=9<BR>\n" );
document.write( "9 = 9^2 - 72<BR>\n" );
document.write( "9 = 81 - 72<BR>\n" );
document.write( "x=-8<BR>\n" );
document.write( "-8 = -8^2 - 72<BR>\n" );
document.write( "-8 = +64 - 72 </SPAN>\n" );
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