document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=65600>Question 65600</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/093979862x/algebrahomeworkh>An Incremental Development</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Solve\r<BR>\n" );
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document.write( " 1/4x - 1/5y = 2<BR>\n" );
document.write( " 0.03x - 0.4y = -1.64\r<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 #46285 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=46285\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve <BR>\n" );
document.write( "(1)  1/4x - 1/5y = 2<BR>\n" );
document.write( "(2)  0.03x - 0.4y = -1.64 \r<BR>\n" );
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document.write( "First, we'll convert (1) from fractions to decimals:<BR>\n" );
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document.write( "(1a)  0.25x - 0.2y = 2<BR>\n" );
document.write( "(2)   0.03x - 0.4y = -1.64 \r<BR>\n" );
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document.write( "Now we could multiply every term in both equations by 100.  That would get rid of the decimals but we really don't need to do that to solve the problem:\r<BR>\n" );
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document.write( "Next, multiply (1a) by 2 and we get:\r<BR>\n" );
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document.write( "(1b)  0.50x - 0.4y = 4<BR>\n" );
document.write( "(2)   0.03x - 0.4y = -1.64 \r<BR>\n" );
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document.write( "Now, subtract (2) from (1b) and we have<BR>\n" );
document.write( "0.47x =5.64<BR>\n" );
document.write( "x=12\r<BR>\n" );
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document.write( "Substitute x=12 in (1a) above:\r<BR>\n" );
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document.write( "(1)  0.25(12) - 0.2y = 2 simplifying, we have\r<BR>\n" );
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document.write( "3-0.2y=2 subtract 3 from both sides<BR>\n" );
document.write( "-0.2y=2-3<BR>\n" );
document.write( "-0.2y=-1<BR>\n" );
document.write( "y=5\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "Now substitute x=12 and y=5 in (1) above<BR>\n" );
document.write( "(1/4)(12)-(1/5)(5)=2<BR>\n" );
document.write( "3-1=2<BR>\n" );
document.write( "2=2<BR>\n" );
document.write( "Substitute in (2)<BR>\n" );
document.write( "0.03(12) - 0.4(5) = -1.64 <BR>\n" );
document.write( ".36-2=-1.64<BR>\n" );
document.write( "-1.64=-1.64\r<BR>\n" );
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document.write( "Hope this helps------ptaylor\r<BR>\n" );
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