document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=893815>Question 893815</A>: <I><SPAN STYLE=\"word-break: break-all;\"> My question is on rational expressions. I can't figure out the steps to take to simplify this expression. (a^(-4)-b^(-4))/(a^(-2)-b^(-2)) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #541526 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=541526\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28a%5E%28-4%29-b%5E%28-4%29%29%2F%28a%5E%28-2%29-b%5E%28-2%29%29+ ALIGN=MIDDLE  ALT=\"+%28a%5E%28-4%29-b%5E%28-4%29%29%2F%28a%5E%28-2%29-b%5E%28-2%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Make the substitutions:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5E%28-2%29+=+1%2Fa%5E2+ ALIGN=MIDDLE  ALT=\"+a%5E%28-2%29+=+1%2Fa%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5E%28-4%29+=+1%2Fa%5E4+ ALIGN=MIDDLE  ALT=\"+a%5E%28-4%29+=+1%2Fa%5E4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b%5E%28-2%29+=+1%2Fb%5E2+ ALIGN=MIDDLE  ALT=\"+b%5E%28-2%29+=+1%2Fb%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b%5E%28-4%29+=+1%2Fb%5E4+ ALIGN=MIDDLE  ALT=\"+b%5E%28-4%29+=+1%2Fb%5E4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+1%2Fa%5E4+-+1%2Fb%5E4+%29+%2F+%28+1%2Fa%5E2+-+1%2Fb%5E2+%29+ ALIGN=MIDDLE  ALT=\"+%28+1%2Fa%5E4+-+1%2Fb%5E4+%29+%2F+%28+1%2Fa%5E2+-+1%2Fb%5E2+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "Now multiply top and bottom by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5E4b%5E4+ ALIGN=MIDDLE  ALT=\"+a%5E4b%5E4+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28%28+a%5E4b%5E4+%29+%2F+%28+a%5E4b%5E4+%29%29%2A%28%28+1%2Fa%5E4+-+1%2Fb%5E4+%29+%2F+%28+1%2Fa%5E2+-+1%2Fb%5E2+%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+b%5E4+-+a%5E4+%29+%2F+%28+a%5E2b%5E4+-+a%5E4b%5E2+%29+ ALIGN=MIDDLE  ALT=\"+%28+b%5E4+-+a%5E4+%29+%2F+%28+a%5E2b%5E4+-+a%5E4b%5E2+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28%28+b%5E2+-+a%5E2+%29%2A%28+b%5E2+%2B+a%5E2+%29%29+%2F+%28%28+a%5E2b%5E2+%29%2A%28+b%5E2+-+a%5E2+%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+b%5E2+%2B+a%5E2+%29+%2F+%28+a%5E2b%5E2+%29+ ALIGN=MIDDLE  ALT=\"+%28+b%5E2+%2B+a%5E2+%29+%2F+%28+a%5E2b%5E2+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++b%5E2+%2F+%28+a%5E2b%5E2+%29+%2B+a%5E2+%2F+%28+a%5E2b%5E2+%29+ ALIGN=MIDDLE  ALT=\"++b%5E2+%2F+%28+a%5E2b%5E2+%29+%2B+a%5E2+%2F+%28+a%5E2b%5E2+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1%2Fa%5E2+%2B+1%2Fb%5E2+ ALIGN=MIDDLE  ALT=\"+1%2Fa%5E2+%2B+1%2Fb%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "or, <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a%5E%28-2%29+%2B+b%5E%28-2%29+ ALIGN=MIDDLE  ALT=\"+a%5E%28-2%29+%2B+b%5E%28-2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------------<BR>\n" );
document.write( "You can do a quick check by plugging<BR>\n" );
document.write( "numbers into original and final answer, like<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+=+3+ ALIGN=MIDDLE  ALT=\"+a+=+3+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+5+ ALIGN=MIDDLE  ALT=\"+b+=+5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and use calculator<BR>\n" );
document.write( "Hope this helps\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );