document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171715>Question 171715</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321233832/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> I got three different answer can someone please put me on the right track \r<BR>\n" );
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document.write( "thank you in advance.\r<BR>\n" );
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document.write( "Walt made an extra $9000 last year from a part-time job. He invested part of the money at 9% and the rest at 8%. He made a total of $770 in interest. How much was invested at 8%?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #126859 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=126859\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Interest(I)=Principal(P)*Rate(R)*Time(T)\r<BR>\n" );
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document.write( "Let x=amount invested at 8%<BR>\n" );
document.write( "Then 9000-x=amount invested at 9%<BR>\n" );
document.write( "Interest at 8%=x*0.08*1=0.08x<BR>\n" );
document.write( "Interest at 9%=(9000-x)*0.09*1=0.09(9000-x)<BR>\n" );
document.write( "And we are told that the above interest adds up to 770, so:<BR>\n" );
document.write( "0.08x+0.09(9000-x)=770  get rid of parens<BR>\n" );
document.write( "0.08x+810-0.09x=770  subtract 810 from each side<BR>\n" );
document.write( "0.08x+810-810-0.09x=770-810  collect like terms<BR>\n" );
document.write( "-0.01x=-40  divide each side by-0.01<BR>\n" );
document.write( "x=$4000--------------------amount invested at 8%<BR>\n" );
document.write( "9000-x=9000-4000=$5000---------amount invested at 9%<BR>\n" );
document.write( "CK<BR>\n" );
document.write( "0.08*4000+0.09*5000=770<BR>\n" );
document.write( "320+450=770<BR>\n" );
document.write( "770=770\r<BR>\n" );
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document.write( "Hope this helps---ptaylor<BR>\n" );
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