document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=350620>Question 350620</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I just took a math test and wanted to see if I had done this right.\r<BR>\n" );
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document.write( "10.  Factor<BR>\n" );
document.write( "     512y^3-729\r<BR>\n" );
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document.write( "I determined that each side of this expression was a cube.  8^3=512, 9^3=729.  So I answered:  (8y x 8y x 8y)-(9 x 9 x 9).  Was this correct? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #250611 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=250611\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hate to be a bearer of bad news but you didn't get it right.<BR>\n" );
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document.write( "512y^3-729<BR>\n" );
document.write( "can be rewritten (as you say) as:<BR>\n" );
document.write( "(8y)^3-9^3<BR>\n" );
document.write( "At this point you have a \"difference of cubes\" -- a special case for factoring:<BR>\n" );
document.write( "a^3 – b^3 = (a – b)(a^2 + ab + b^2)<BR>\n" );
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document.write( "which then gives you:<BR>\n" );
document.write( "(8y - 9)((8y)^2 + (8y)(9) + 9^2)<BR>\n" );
document.write( "(8y - 9)(64y^2 + 72y + 81)<BR>\n" );
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