document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=987452>Question 987452</A>: <I><SPAN STYLE=\"word-break: break-all;\"> for the following equation I need to solve for all valid value(s) of x:\r<BR>\n" );
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document.write( "3x-1= Sqrt 9x^2+9\r<BR>\n" );
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document.write( "After simplifying and solving for x I got -1.5 for the value of x\r<BR>\n" );
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document.write( "However when this is plugged into the equation it gives a negative value under the square root, which should make the value invalid.\r<BR>\n" );
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document.write( "I don't know whether I made a mistake in my working, or if -1.5 is for some reason a valid answer (do i need to use imaginary numbers??)\r<BR>\n" );
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document.write( "So really the whole question is a bit of a confusion for me, could anyone confirm that x= -1.5, and that there are no valid values for this problem? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #608233 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=608233\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3x -1 = Sqrt(9x^2+9) <BR>\n" );
document.write( "square both sides of the =<BR>\n" );
document.write( "9x^2 - 6x + 1 = 9x^2 + 9<BR>\n" );
document.write( "subtract 9x^2 from both sides of =<BR>\n" );
document.write( "-6x + 1 = 9<BR>\n" );
document.write( "subtract 1 fro both sides of =<BR>\n" );
document.write( "-6x = 8<BR>\n" );
document.write( "x = -1.333333333  <BR>\n" );
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document.write( "check the answer<BR>\n" );
document.write( "3(-1.333333333) - 1 = Sqrt(9(-1.333333333^2) +9)<BR>\n" );
document.write( "-5 = + or - (4.99999999999)<BR>\n" );
document.write( "therefore,<BR>\n" );
document.write( "-5 approx -5<BR>\n" );
document.write( "our answer checks,<BR>\n" );
document.write( "x = -1.333333333 <BR>\n" );
document.write( "note that the answer becomes positive when squared<BR>\n" );
document.write( "  </SPAN>\n" );
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