document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=475234>Question 475234</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am in college algebra online and we have a study sheet of problems which we need to know how to solve one similar. The one I am having trouble with is (1+r)^4=3.6  I had started by factoring but I was lost at what to do after I factored it out. I have r^4+4r^3+6r^2+4r+1=3.6 then subtracted 1 to get r^4+4r^3+6r^2+4r=2.6 now I am stuck. Thank you in advanced. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #325858 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20059)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=325858\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> </pre><BR>\n" );
document.write( "You used the word \"factoring\" wrong. You said \"I started by factoring\".<BR>\n" );
document.write( "But what you did was exactly the opposite of factoring.  The left side<BR>\n" );
document.write( "of the equation was ALREADY factored.  What you did was \"un-factor\" it by<BR>\n" );
document.write( "multiplying it out.  But you shouldn't have done that.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2Br%29%5E4=3.6 ALIGN=MIDDLE  ALT=\"%281%2Br%29%5E4=3.6\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Don't multiply that out. Instead take the root of both sides <BR>\n" );
document.write( "with the same index as the exponent of the left side.  That is,<BR>\n" );
document.write( "take the 4th root of both sides.  Now since 4 is even we must <BR>\n" );
document.write( "get both the positive as well as the negative 4th root, so we <BR>\n" );
document.write( "have this\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=root%284%2C%281%2Br%29%5E4%29+=+%22%22+%2B-+root%284%2C3.6%29+ ALIGN=MIDDLE  ALT=\"root%284%2C%281%2Br%29%5E4%29+=+%22%22+%2B-+root%284%2C3.6%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "The fourth root and the fourth power cancel on the left and we have<BR>\n" );
document.write( "just \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Br+=+%22%22+%2B-+root%284%2C3.6%29+ ALIGN=MIDDLE  ALT=\"1%2Br+=+%22%22+%2B-+root%284%2C3.6%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solve for r:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+-1+%2B-+root%284%2C3.6%29 ALIGN=MIDDLE  ALT=\"r+=+-1+%2B-+root%284%2C3.6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "We have two solutions, one using the + and one using the -.\r<BR>\n" );
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document.write( "Using the + :\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+-1+%2B+root%284%2C3.6%29 ALIGN=MIDDLE  ALT=\"r+=+-1+%2B+root%284%2C3.6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  which you can approximate with<BR>\n" );
document.write( "a calculator as\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+-1+%2B+1.377449308 ALIGN=MIDDLE  ALT=\"r+=+-1+%2B+1.377449308\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+0.377449308 ALIGN=MIDDLE  ALT=\"r+=+0.377449308\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Using the + :\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+-1+-+root%284%2C3.6%29 ALIGN=MIDDLE  ALT=\"r+=+-1+-+root%284%2C3.6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  which you can approximate with<BR>\n" );
document.write( "a calculator as\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+-1+-+1.377449308 ALIGN=MIDDLE  ALT=\"r+=+-1+-+1.377449308\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+-2.377449308 ALIGN=MIDDLE  ALT=\"r+=+-2.377449308\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <BR>\n" );
document.write( "Edwin</pre>\r<BR>\n" );
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