document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=180326>Question 180326</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help me solve this problem?!!?  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9x%5E4=25x%5E2-16 ALIGN=MIDDLE  ALT=\"9x%5E4=25x%5E2-16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The directions say:  solve the equation by making the appropriate substitution.<BR>\n" );
document.write( "Here is what I have so far....but I am stuck.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283x%5E2%29%5E2-25x%5E2%2B16=0 ALIGN=MIDDLE  ALT=\"%283x%5E2%29%5E2-25x%5E2%2B16=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3u%5E2-25u%2B16=0 ALIGN=MIDDLE  ALT=\"3u%5E2-25u%2B16=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "At this point I wasn't sure.  Do I use the quadratic formula???  I tried that but just got confused.  Please help.  Thanks. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #135151 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=135151\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 9x^4=25x^2-16\r<BR>\n" );
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document.write( "9x^4 - 25x^2 + 16 = 0\r<BR>\n" );
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document.write( "Quadratic Formula:\r<BR>\n" );
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document.write( "x^2 = [25 +- sqrt(625 - 4*9*+16)]/18\r<BR>\n" );
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document.write( "x^2 = [25 +- sqrt(49)]/18\r<BR>\n" );
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document.write( "x^2 = [25 + 7]/18 or x^2 = [25 - 7]/18\r<BR>\n" );
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document.write( "x^2 = 16/9 or x^2 = 1\r<BR>\n" );
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document.write( "x = (4/3) or x = (-4/3) or x = 1 or x= -1<BR>\n" );
document.write( "===============================================<BR>\n" );
document.write( "Cheers<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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