document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=302148>Question 302148</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For the given rational function f, find all values of x for which f(x) has the indicated value.<BR>\n" );
document.write( "	f(x) =  5x + 21/x  ; f(x) = -38   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #216684 by </B><A HREF=/tutors/aboutme.mpl?userid=london+maths+tutor><B>london maths tutor(243)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=london+maths+tutor><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=london+maths+tutor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=216684\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 	f(x) =  5x + 21/x  ; f(x) = -38 \r<BR>\n" );
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document.write( "-38 = 5x + (21/x)<BR>\n" );
document.write( "-38x = 5x^2 + 21<BR>\n" );
document.write( "5x^2 + 38x + 21 = 0<BR>\n" );
document.write( "(5x + 3)(x + 7) = 0 \r<BR>\n" );
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document.write( "Therefore,<BR>\n" );
document.write( "5x+3 = 0 <BR>\n" );
document.write( "x = -3/5\r<BR>\n" );
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document.write( "or <BR>\n" );
document.write( "x+7 = 0<BR>\n" );
document.write( "x=-7\r<BR>\n" );
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document.write( "Answer: x = -3/5 and -7  </SPAN>\n" );
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