document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=37285>Question 37285</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321233883/algebrahomeworkh>Elementary Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Please help factor completely<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Please+help+factor+completely%0D%0A ALIGN=MIDDLE  ALT=\"Please+help+factor+completely%0D%0A\"   DISABLED_style= \"max-width:90%; height:auto;\" > b^4a-81a^5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #23027 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=23027\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First let us factor out an \"a\" as our common factor, so that<BR>\n" );
document.write( "b^4a - 81a^5 =<BR>\n" );
document.write( "a(b^4 - 81a^4) =<BR>\n" );
document.write( "Now we have the difference of squares, and that factors out to<BR>\n" );
document.write( "a(b^2 + 9a^2)(b^2 - 9a^2) =<BR>\n" );
document.write( "But this last term factors out once more as the difference of squares, and we have<BR>\n" );
document.write( "a(b^2 + 9a^2)(b + 3a)(b - 3a) </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );