document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1164447>Question 1164447</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The problem is 8x^3=125. Why can't I simply take the cubed root of both sides to get 2x=5, and from there get x=5/2?\r<BR>\n" );
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document.write( "The solutions I have seen require I move all terms to the left and set the equation equal to zero, factor using difference of cubes formula, and solve from there, giving me x= 5/2, and x=-5+/-5i(square root of 3) all over 4. I don't understand why I can't just solve it as the equation is given, instead of setting everything to 0. Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #788842 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=788842\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
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document.write( "In this concrete case, &nbsp;you can.\r<BR>\n" );
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document.write( "In this case, &nbsp;until you restrict yourself by real numbers, &nbsp;you can.\r<BR>\n" );
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document.write( "In more complicated cases, &nbsp;the cubic root from a number is a &nbsp;<U>complex number</U>, &nbsp;and even not one complex number,\r<BR>\n" );
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document.write( "but THREE, &nbsp;instead.\r<BR>\n" );
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document.write( "So, &nbsp;in this complex case, &nbsp;after taking the cubic root, &nbsp;you may have &nbsp;3 &nbsp;values of the cubic root on the left side \r<BR>\n" );
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document.write( "and &nbsp;3 &nbsp;cubic root values on the right side --- and how then you will decide who is equal to whom ?\r<BR>\n" );
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document.write( "It is the story . . . \r<BR>\n" );
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document.write( "After reading the post by tutor @MathTherapy.\r<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "    When you take the CUBE ROOT, you DO NOT NEED to write +-.\r\n" );
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document.write( "    Until you work with real numbers, keep the sign of the resulting real number (cube root) \r\n" );
document.write( "    SAME as the number UNDER the cube root sign.\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( "The post by @MathTherapy is a mistake.\r<BR>\n" );
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document.write( "  </SPAN>\n" );
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